Files
mercury/compiler/prog_io.m
Julien Fischer 0bb49f40d2 Fix one of the problems that causes the compiler to run out of stack
Estimated hours taken: 2
Branches: main

Fix one of the problems that causes the compiler to run out of stack
space when compiling a discriminated unions that has a large numbers of
constructors.  This speeds up compilation of a type with 200000 constructors
by about 1% -- it doesn't have a measurable impact on discriminated unions
of a more usual size.

compiler/prog_io.m:
	When checking that the constructors of a discriminated union
	are well-formed, iterate through the list of constructors once instead
	of four times.
2007-11-14 14:15:16 +00:00

4466 lines
170 KiB
Mathematica

%-----------------------------------------------------------------------------e
% vim: ft=mercury ts=4 sw=4 et
%-----------------------------------------------------------------------------e
% Copyright (C) 1993-2007 The University of Melbourne.
% This file may only be copied under the terms of the GNU General
% Public License - see the file COPYING in the Mercury distribution.
%-----------------------------------------------------------------------------%
%
% File: prog_io.m.
% Main authors: fjh, zs.
%
% This module defines predicates for parsing Mercury programs.
%
% In some ways the representation of programs here is considerably
% more complex than is necessary for the compiler.
% The basic reason for this is that it was designed to preserve
% as much information about the source code as possible, so that
% this representation could also be used for other tools such
% as pretty-printers.
% Currently the only information that is lost is that comments and
% whitespace are stripped, any redundant parenthesization
% are lost, distinctions between different spellings of the same
% operator (eg "\+" vs "not") are lost, and DCG clauses get expanded.
% It would be a good idea to preserve all those too (well, maybe not
% the redundant parentheses), but right now it's not worth the effort.
%
% So that means that this phase of compilation is purely parsing.
% No simplifications are done (other than DCG expansion).
% The results of this phase specify
% basically the same information as is contained in the source code,
% but in a parse tree rather than a flat file.
% Simplifications are done only by make_hlds.m, which transforms
% the parse tree which we built here into the HLDS.
%
% Some of this code is a rather bad example of cut-and-paste style reuse.
% It should be cleaned up to eliminate most of the duplication.
% But that task really needs to wait until we implement higher-order
% predicates. For the moment, just be careful that any changes
% you make are reflected correctly in all similar parts of this file.
%
% Implication and equivalence implemented by squirrel, who would also
% like to get her hands on this file and give it a good clean up and
% put it into good clean "mercury" style!
%
% Wishlist:
%
% 1. implement importing/exporting operators with a particular fixity
% eg. :- import_op prefix(+). % only prefix +, not infix
% (not important, but should be there for reasons of symmetry.)
% 2. improve the handling of type and inst parameters
% 3. improve the error reporting (most of the semidet preds should
% be det and should return a meaningful indication of where an
% error occurred).
%-----------------------------------------------------------------------------%
:- module parse_tree.prog_io.
:- interface.
:- import_module libs.timestamp.
:- import_module mdbcomp.prim_data.
:- import_module parse_tree.prog_data.
:- import_module parse_tree.prog_item.
:- import_module parse_tree.prog_io_util.
:- import_module bool.
:- import_module io.
:- import_module list.
:- import_module maybe.
:- import_module term.
:- import_module varset.
%-----------------------------------------------------------------------------%
% This module (prog_io) exports the following predicates:
:- type file_name == string.
:- type dir_name == string.
% Open a source or interface file, returning `ok(FileInfo)' on success
% (where FileInfo is information about the file such as the file name
% or the directory in which it was found), or `error(Message)' on failure.
:- type open_file(FileInfo) == pred(maybe_error(FileInfo), io, io).
:- inst open_file == (pred(out, di, uo) is det).
:- type module_error
---> no_module_errors % no errors
; some_module_errors % some syntax errors
; fatal_module_errors. % couldn't open the file
% read_module(OpenFile, FileName, DefaultModuleName, ReturnTimestamp,
% Error, MaybeFileInfo, ActualModuleName, Messages, Program,
% MaybeModuleTimestamp, !IO):
%
% Reads and parses the file opened by OpenFile using the default module
% name DefaultModuleName. If ReturnTimestamp is `yes', attempt to return
% the modification timestamp in MaybeModuleTimestamp. Error is
% `fatal_module_errors' if the file coudn't be opened, `some_module_errors'
% if a syntax error was detected, and `no_module_errors' otherwise.
% MaybeFileInfo is the information about the file (usually the file or
% directory name) returned by OpenFile. ActualModuleName is the module name
% specified in the `:- module' declaration, if any, or the
% DefaultModuleName if there is no `:- module' declaration.
% Messages is a list of warning/error messages. Program is the parse tree.
%
:- pred read_module(open_file(FileInfo)::in(open_file),
module_name::in, bool::in, module_error::out, maybe(FileInfo)::out,
module_name::out, message_list::out, item_list::out,
maybe(io.res(timestamp))::out, io::di, io::uo) is det.
:- pred read_module_if_changed(open_file(FileInfo)::in(open_file),
module_name::in, timestamp::in, module_error::out,
maybe(FileInfo)::out, module_name::out, message_list::out,
item_list::out, maybe(io.res(timestamp))::out, io::di, io::uo) is det.
% Same as read_module, but use intermod_directories instead of
% search_directories when searching for the file.
% Also report an error if the actual module name doesn't match
% the expected module name.
%
:- pred read_opt_file(file_name::in, module_name::in, module_error::out,
message_list::out, item_list::out, io::di, io::uo) is det.
% check_module_has_expected_name(FileName, ExpectedName, ActualName):
%
% Check that two module names are equal, and report an error if they
% aren't.
%
:- pred check_module_has_expected_name(file_name::in, module_name::in,
module_name::in, io::di, io::uo) is det.
% search_for_file(Dirs, FileName, FoundFileName, !IO):
%
% Search Dirs for FileName, opening the file if it is found,
% and returning the path name of the file that was found.
%
:- pred search_for_file(list(dir_name)::in, file_name::in,
maybe_error(file_name)::out, io::di, io::uo) is det.
% search_for_file_returning_dir(Dirs, FileName, FoundDirName, !IO):
%
% Search Dirs for FileName, opening the file if it is found, and returning
% the name of the directory in which the file was found.
%
:- pred search_for_file_returning_dir(list(dir_name)::in, file_name::in,
maybe_error(dir_name)::out, io::di, io::uo) is det.
% search_for_module_source(Dirs, InterfaceDirs, ModuleName,
% FoundSourceFileName, !IO):
%
% Look for the source for ModuleName in Dirs. This will also search for
% files matching partially qualified versions of ModuleName, but only if
% a more qualified `.m' or `.int' file doesn't exist in InterfaceDirs.
% in InterfaceDirs. For example, module foo.bar.baz can be found in
% foo.bar.m, bar.baz.m or bar.m.
%
:- pred search_for_module_source(list(dir_name)::in, list(dir_name)::in,
module_name::in, maybe_error(file_name)::out, io::di, io::uo) is det.
% Read the first item from the given file to find the module name.
%
:- pred find_module_name(file_name::in, maybe(module_name)::out,
io::di, io::uo) is det.
% parse_item(ModuleName, VarSet, Term, MaybeItem):
%
% Parse Term. If successful, MaybeItem is bound to the parsed item,
% otherwise it is bound to an appropriate error message. Qualify
% appropriate parts of the item, with ModuleName as the module name.
%
:- pred parse_item(module_name::in, varset::in, term::in,
maybe_item_and_context::out) is det.
% parse_decl(ModuleName, VarSet, Term, Result):
%
% Parse Term as a declaration. If successful, Result is bound to the
% parsed item, otherwise it is bound to an appropriate error message.
% Qualify appropriate parts of the item, with ModuleName as the module
% name.
%
:- pred parse_decl(module_name::in, varset::in, term::in,
maybe_item_and_context::out) is det.
% parse_type_defn_head(ModuleName, Head, Body, HeadResult):
%
% Check the head of a type definition for errors.
%
:- pred parse_type_defn_head(module_name::in, term::in, term::in,
maybe2(sym_name, list(type_param))::out) is det.
% parse_type_decl_where_part_if_present(TypeSymName, Arity,
% IsSolverType, Inst, ModuleName, Term0, Term, Result):
%
% Checks if Term0 is a term of the form `<body> where <attributes>'.
% If so, returns the `<body>' in Term and the parsed `<attributes>'
% in Result. If not, returns Term = Term0 and Result = no.
%
:- pred parse_type_decl_where_part_if_present(is_solver_type::in,
module_name::in, term::in, term::out,
maybe2(maybe(solver_type_details), maybe(unify_compare))::out) is det.
%-----------------------------------------------------------------------------%
% A QualifiedTerm is one of
% Name(Args)
% Module.Name(Args)
% (or if Args is empty, one of
% Name
% Module.Name)
% where Module is a SymName. For backwards compatibility, we allow `__'
% as an alternative to `.'.
% Sym_name_and_args takes a term and returns a sym_name and a list of
% argument terms. It fails if the input is not valid syntax for a
% QualifiedTerm.
%
:- pred sym_name_and_args(term(T)::in, sym_name::out, list(term(T))::out)
is semidet.
% parse_qualified_term/4 takes a term (and also the containing term,
% and a string describing the context from which it was called
% [e.g. "clause head"]) and returns a sym_name and a list of argument
% terms. Returns an error on ill-formed input. See also
% parse_implicitly_qualified_term/5 (below).
%
:- pred parse_qualified_term(term(T)::in, term(T)::in, string::in,
maybe_functor(T)::out) is det.
% parse_implicitly_qualified_term(DefaultModName, Term,
% ContainingTerm, Msg, Result):
%
% parse_implicitly_qualified_term/5 takes a default module name and a term,
% (and also the containing term, and a string describing the context from
% which it was called (e.g. "clause head"), and returns a sym_name and
% a list of argument terms. Returns an error on ill-formed input or
% a module qualifier that doesn't match the DefaultModName.
%
% Note: parse_qualified_term/4 is used for places where a symbol is _used_,
% in which case no default module name exists, whereas
% parse_implicitly_qualified_term/5 is used for places where a symbol
% is _defined_; in that case, there is a default module name (the name
% of the current module) -- specifying a module qualifier explicitly
% is redundant, but it is allowed, so long as the module qualifier
% specified matches the default.
%
:- pred parse_implicitly_qualified_term(module_name::in, term(T)::in,
term(T)::in, string::in, maybe_functor(T)::out) is det.
%-----------------------------------------------------------------------------%
% Replace all occurrences of inst_var(I) with
% constrained_inst_var(I, ground(shared, none)).
%
:- pred constrain_inst_vars_in_mode(mer_mode::in, mer_mode::out) is det.
% Replace all occurrences of inst_var(I) with
% constrained_inst_var(I, Inst) where I -> Inst is in the inst_var_sub.
% If I is not in the inst_var_sub, default to ground(shared, none).
%
:- pred constrain_inst_vars_in_mode(inst_var_sub::in,
mer_mode::in, mer_mode::out) is det.
%-----------------------------------------------------------------------------%
% Check that for each constrained_inst_var all occurrences have the
% same constraint.
%
:- pred inst_var_constraints_are_consistent_in_modes(list(mer_mode)::in)
is semidet.
%-----------------------------------------------------------------------------%
%-----------------------------------------------------------------------------%
:- implementation.
:- import_module libs.compiler_util.
:- import_module libs.globals.
:- import_module libs.options.
:- import_module parse_tree.modules.
:- import_module parse_tree.modules.
:- import_module parse_tree.error_util.
:- import_module parse_tree.prog_io_dcg.
:- import_module parse_tree.prog_io_goal.
:- import_module parse_tree.prog_io_pragma.
:- import_module parse_tree.prog_io_typeclass.
:- import_module parse_tree.prog_io_util.
:- import_module parse_tree.prog_mode.
:- import_module parse_tree.prog_out.
:- import_module parse_tree.prog_type.
:- import_module parse_tree.prog_util.
:- import_module recompilation.
:- import_module recompilation.version.
:- import_module assoc_list.
:- import_module dir.
:- import_module int.
:- import_module map.
:- import_module pair.
:- import_module parser.
:- import_module set.
:- import_module string.
:- import_module term_io.
:- import_module unit.
%-----------------------------------------------------------------------------%
read_module(OpenFile, DefaultModuleName, ReturnTimestamp, Error,
FileData, ModuleName, Messages, Items, MaybeModuleTimestamp, !IO) :-
read_module_2(OpenFile, DefaultModuleName, no, ReturnTimestamp, Error,
FileData, ModuleName, Messages, Items, MaybeModuleTimestamp, !IO).
read_module_if_changed(OpenFile, DefaultModuleName, OldTimestamp, Error,
FileData, ModuleName, Messages, Items, MaybeModuleTimestamp, !IO) :-
read_module_2(OpenFile, DefaultModuleName, yes(OldTimestamp), yes, Error,
FileData, ModuleName, Messages, Items, MaybeModuleTimestamp, !IO).
read_opt_file(FileName, DefaultModuleName, Error, Messages, Items, !IO) :-
globals.io_lookup_accumulating_option(intermod_directories, Dirs, !IO),
read_module_2(search_for_file(Dirs, FileName), DefaultModuleName, no, no,
Error, _, ModuleName, Messages, Items, _, !IO),
check_module_has_expected_name(FileName, DefaultModuleName, ModuleName,
!IO).
check_module_has_expected_name(FileName, ExpectedName, ActualName, !IO) :-
( ActualName \= ExpectedName ->
Pieces = [words("Error: file"), quote(FileName),
words("contains the wrong module."), nl,
words("Expected module"), sym_name(ExpectedName), suffix(","),
words("found module"), sym_name(ActualName), suffix("."), nl],
write_error_pieces_plain(Pieces, !IO),
io.set_exit_status(1, !IO)
;
true
).
% This implementation uses io.read_term to read in the program one term
% at a time, and then converts those terms into clauses and declarations,
% checking for errors as it goes. Note that rather than using difference
% lists, we just build up the lists of items and messages in reverse order
% and then reverse them afterwards. (Using difference lists would require
% late-input modes.)
%
:- pred read_module_2(open_file(T)::in(open_file), module_name::in,
maybe(timestamp)::in, bool::in, module_error::out, maybe(T)::out,
module_name::out, message_list::out, item_list::out,
maybe(io.res(timestamp))::out, io::di, io::uo) is det.
read_module_2(OpenFile, DefaultModuleName, MaybeOldTimestamp, ReturnTimestamp,
Error, MaybeFileData, ModuleName, Messages, Items,
MaybeModuleTimestamp, !IO) :-
io.input_stream(OldInputStream, !IO),
OpenFile(OpenResult, !IO),
(
OpenResult = ok(FileData),
MaybeFileData = yes(FileData),
( ReturnTimestamp = yes ->
io.input_stream_name(InputStreamName, !IO),
io.file_modification_time(InputStreamName, TimestampResult, !IO),
(
TimestampResult = ok(Timestamp),
MaybeModuleTimestamp = yes(ok(time_t_to_timestamp(Timestamp)))
;
TimestampResult = error(IOError),
MaybeModuleTimestamp = yes(error(IOError))
)
;
MaybeModuleTimestamp = no
),
(
MaybeOldTimestamp = yes(OldTimestamp),
MaybeModuleTimestamp = yes(ok(OldTimestamp))
->
% XXX Currently smart recompilation won't work
% if ModuleName \= DefaultModuleName.
% In that case, smart recompilation will be disabled
% and read_module should never be passed an old timestamp.
ModuleName = DefaultModuleName,
Items = [],
Error = no_module_errors,
Messages = []
;
read_all_items(DefaultModuleName, ModuleName, Messages, Items,
Error, !IO)
),
io.set_input_stream(OldInputStream, ModuleInputStream, !IO),
io.close_input(ModuleInputStream, !IO)
;
OpenResult = error(Message0),
io.progname_base("mercury_compile", Progname, !IO),
Message = Progname ++ ": " ++ Message0,
dummy_term(Term),
Messages = [Message - Term],
Error = fatal_module_errors,
Items = [],
ModuleName = DefaultModuleName,
MaybeFileData = no,
MaybeModuleTimestamp = no
).
search_for_file(Dirs, FileName, Result, !IO) :-
search_for_file_returning_dir(Dirs, FileName, Result0, !IO),
(
Result0 = ok(Dir),
( dir.this_directory(Dir) ->
PathName = FileName
;
PathName = dir.make_path_name(Dir, FileName)
),
Result = ok(PathName)
;
Result0 = error(Message),
Result = error(Message)
).
search_for_file_returning_dir(Dirs, FileName, R, !IO) :-
search_for_file_returning_dir(Dirs, Dirs, FileName, R, !IO).
:- pred search_for_file_returning_dir(list(dir_name)::in, list(dir_name)::in,
file_name::in, maybe_error(dir_name)::out, io::di, io::uo) is det.
search_for_file_returning_dir([], AllDirs, FileName, error(Msg), !IO) :-
Msg = "cannot find `" ++ FileName ++ "' in directories " ++
string.join_list(", ", AllDirs).
search_for_file_returning_dir([Dir | Dirs], AllDirs, FileName, R, !IO) :-
( dir.this_directory(Dir) ->
ThisFileName = FileName
;
ThisFileName = dir.make_path_name(Dir, FileName)
),
io.see(ThisFileName, R0, !IO),
( R0 = ok ->
R = ok(Dir)
;
search_for_file_returning_dir(Dirs, AllDirs, FileName, R, !IO)
).
search_for_module_source(Dirs, InterfaceDirs,
ModuleName, MaybeFileName, !IO) :-
search_for_module_source_2(Dirs, ModuleName, ModuleName,
MaybeFileName0, !IO),
(
MaybeFileName0 = ok(SourceFileName),
(
string.remove_suffix(dir.basename(SourceFileName),
".m", SourceFileBaseName),
file_name_to_module_name(SourceFileBaseName, SourceFileModuleName),
ModuleName \= SourceFileModuleName
->
% The module name doesn't match the file name. Return an error
% if there is a more qualified matching `.m' or `.int' file in
% the interface search path. This avoids having a file `read.m'
% in the current directory prevent the compiler from finding
% `bit_buffer.read.int' in the standard library.
%
io.input_stream(SourceStream, !IO),
search_for_module_source_2(InterfaceDirs, ModuleName,
ModuleName, MaybeFileName2, !IO),
( MaybeFileName2 = ok(_) ->
io.seen(!IO)
;
true
),
(
MaybeFileName2 = ok(SourceFileName2),
SourceFileName2 \= SourceFileName,
string.remove_suffix(dir.basename(SourceFileName2), ".m",
SourceFileBaseName2),
file_name_to_module_name(SourceFileBaseName2,
SourceFileModuleName2),
match_sym_name(SourceFileModuleName, SourceFileModuleName2)
->
io.close_input(SourceStream, !IO),
MaybeFileName = error(find_source_error(ModuleName,
Dirs, yes(SourceFileName2)))
;
module_name_to_file_name(ModuleName, ".int", no, IntFile, !IO),
search_for_file_returning_dir(InterfaceDirs, IntFile,
MaybeIntDir, !IO),
( MaybeIntDir = ok(_) ->
io.seen(!IO)
;
true
),
(
MaybeIntDir = ok(IntDir),
IntDir \= dir.this_directory
->
io.close_input(SourceStream, !IO),
MaybeFileName = error(find_source_error(ModuleName,
Dirs, yes(IntDir/IntFile)))
;
io.set_input_stream(SourceStream, _, !IO),
MaybeFileName = MaybeFileName0
)
)
;
MaybeFileName = MaybeFileName0
)
;
MaybeFileName0 = error(_),
MaybeFileName = MaybeFileName0
).
:- func find_source_error(module_name, list(dir_name),
maybe(file_name)) = string.
find_source_error(ModuleName, Dirs, MaybeBetterMatch) = Msg :-
ModuleNameStr = sym_name_to_string(ModuleName),
Msg0 = "cannot find source for module `" ++ ModuleNameStr ++
"' in directories " ++ string.join_list(", ", Dirs),
(
MaybeBetterMatch = no, Msg = Msg0
;
MaybeBetterMatch = yes(BetterMatchFile),
Msg = Msg0 ++ ", but found " ++ BetterMatchFile
++ " in interface search path"
).
:- pred search_for_module_source_2(list(dir_name)::in, module_name::in,
module_name::in, maybe_error(file_name)::out, io::di, io::uo) is det.
search_for_module_source_2(Dirs, ModuleName, PartialModuleName, Result, !IO) :-
module_name_to_file_name(PartialModuleName, ".m", no, FileName, !IO),
search_for_file(Dirs, FileName, Result0, !IO),
(
Result0 = ok(_),
Result = Result0
;
Result0 = error(_),
(
PartialModuleName1 = drop_one_qualifier(PartialModuleName)
->
search_for_module_source_2(Dirs, ModuleName, PartialModuleName1,
Result, !IO)
;
Result = error(find_source_error(ModuleName, Dirs, no))
)
).
:- func drop_one_qualifier(module_name) = module_name is semidet.
drop_one_qualifier(qualified(ParentQual, ChildName)) =
drop_one_qualifier_2(ParentQual, ChildName).
:- func drop_one_qualifier_2(module_name, string) = module_name.
drop_one_qualifier_2(ParentQual, ChildName) = PartialQual :-
(
ParentQual = unqualified(_ParentName),
PartialQual = unqualified(ChildName)
;
ParentQual = qualified(GrandParentQual, ParentName),
PartialGrandParentQual = drop_one_qualifier_2(GrandParentQual,
ParentName),
PartialQual = qualified(PartialGrandParentQual, ChildName)
).
%-----------------------------------------------------------------------------%
:- type module_end
---> module_end_no
; module_end_yes(module_name, prog_context).
% Extract the final `:- end_module' declaration if any.
%
:- pred get_end_module(module_name::in, item_list::in, item_list::out,
module_end::out) is det.
get_end_module(ModuleName, RevItemAndContexts0, RevItemAndContexts,
EndModule) :-
(
% Note: if the module name in the end_module declaration does not match
% what we expect, given the source file name, then we assume that it is
% for a nested module, and so we leave it alone. If it is not for a
% nested module, the error will be caught by make_hlds.
RevItemAndContexts0 = [item_and_context(Item, Context) |
RevItemAndContextsPrime],
Item = item_module_defn(_VarSet, md_end_module(ModuleName))
->
RevItemAndContexts = RevItemAndContextsPrime,
EndModule = module_end_yes(ModuleName, Context)
;
RevItemAndContexts = RevItemAndContexts0,
EndModule = module_end_no
).
%-----------------------------------------------------------------------------%
% Check that the module starts with a :- module declaration,
% and that the end_module declaration (if any) is correct,
% and construct the final parsing result.
%
:- pred check_end_module(module_end::in, message_list::in, message_list::out,
item_list::in, item_list::out, module_error::in, module_error::out) is det.
check_end_module(EndModule, !Messages, !ItemAndContexts, !Error) :-
% Double-check that the first item is a `:- module ModuleName' declaration,
% and remove it from the front of the item list.
(
!.ItemAndContexts = [ItemAndContext | !:ItemAndContexts],
ItemAndContext = item_and_context(Item, _Context1),
Item = item_module_defn(_VarSet, md_module(ModuleName1))
->
% Check that the end module declaration (if any) matches
% the begin module declaration.
(
EndModule = module_end_yes(ModuleName2, Context2),
ModuleName1 \= ModuleName2
->
dummy_term_with_context(Context2, Term),
Msg = "`:- end_module' declaration doesn't match " ++
"`:- module' declaration",
add_error(Msg - Term, !Messages),
!:Error = some_module_errors
;
true
)
;
% If there's no `:- module' declaration at this point, it is
% an internal error -- read_first_item should have inserted one.
unexpected(this_file,
"check_end_module: no `:- module' declaration")
).
%-----------------------------------------------------------------------------%
% Create a dummy term. Used for error messages that are not associated
% with any particular term or context.
%
:- pred dummy_term(term::out) is det.
dummy_term(Term) :-
term.context_init(Context),
dummy_term_with_context(Context, Term).
% Create a dummy term with the specified context.
% Used for error messages that are associated with some specific
% context, but for which we don't want to print out the term
% (or for which the term isn't available to be printed out).
%
:- pred dummy_term_with_context(term.context::in, term::out) is det.
dummy_term_with_context(Context, Term) :-
Term = term.functor(term.atom(""), [], Context).
%-----------------------------------------------------------------------------%
find_module_name(FileName, MaybeModuleName, !IO) :-
io.open_input(FileName, OpenRes, !IO),
(
OpenRes = ok(InputStream),
io.set_input_stream(InputStream, OldInputStream, !IO),
( string.remove_suffix(FileName, ".m", PartialFileName0) ->
PartialFileName = PartialFileName0
;
PartialFileName = FileName
),
( dir.basename(PartialFileName, BaseName0) ->
BaseName = BaseName0
;
BaseName = ""
),
file_name_to_module_name(BaseName, DefaultModuleName),
read_first_item(DefaultModuleName, FileName, _,
ModuleName, RevMessages, _, _, _, !IO),
MaybeModuleName = yes(ModuleName),
prog_out.write_messages(list.reverse(RevMessages), !IO),
io.set_input_stream(OldInputStream, _, !IO),
io.close_input(InputStream, !IO)
;
OpenRes = error(Error),
io.progname_base("mercury_compile", Progname, !IO),
io.write_string(Progname, !IO),
io.write_string(": error opening `", !IO),
io.write_string(FileName, !IO),
io.write_string("': ", !IO),
io.write_string(io.error_message(Error), !IO),
io.write_string(".\n", !IO),
MaybeModuleName = no
).
% Read a source file from standard in, first reading in
% the input term by term and then parsing those terms and producing
% a high-level representation.
% Parsing is actually a 3-stage process instead of the
% normal two-stage process:
% lexical analysis (chars -> tokens),
% parsing stage 1 (tokens -> terms),
% parsing stage 2 (terms -> items).
% The final stage produces a list of program items, each of which
% may be a declaration or a clause.
%
% We use a continuation-passing style here.
%
:- pred read_all_items(module_name::in, module_name::out, message_list::out,
item_list::out, module_error::out, io::di, io::uo) is det.
read_all_items(DefaultModuleName, ModuleName, Messages, Items, Error, !IO) :-
% Read all the items (the first one is handled specially).
io.input_stream(Stream, !IO),
io.input_stream_name(Stream, SourceFileName0, !IO),
read_first_item(DefaultModuleName, SourceFileName0, SourceFileName,
ModuleName, RevMessages0, RevItems0, MaybeSecondTerm, Error0, !IO),
(
MaybeSecondTerm = yes(SecondTerm),
process_read_term(ModuleName, SecondTerm, MaybeSecondItem),
read_items_loop_2(MaybeSecondItem, ModuleName, SourceFileName,
RevMessages0, RevMessages1, RevItems0, RevItems1,
Error0, Error1, !IO)
;
MaybeSecondTerm = no,
read_items_loop(ModuleName, SourceFileName,
RevMessages0, RevMessages1, RevItems0, RevItems1,
Error0, Error1, !IO)
),
% Get the end_module declaration (if any), check that it matches
% the initial module declaration (if any), and remove both of them
% from the final item list.
get_end_module(ModuleName, RevItems1, RevItems, EndModule),
check_end_module(EndModule, RevMessages1, RevMessages, Items0, Items,
Error1, Error),
list.reverse(RevMessages, Messages),
list.reverse(RevItems, Items0).
% We need to jump through a few hoops when reading the first item,
% to allow the initial `:- module' declaration to be optional.
% The reason is that in order to parse an item, we need to know
% which module it is defined in (because we do some module
% qualification and checking of module qualifiers at parse time),
% but the initial `:- module' declaration and the declaration
% that follows it occur in different scopes, so we need to know
% what it is that we're parsing before we can parse it!
% We solve this dilemma by first parsing it in the root scope,
% and then if it turns out to not be a `:- module' declaration
% we reparse it in the default module scope. Blecchh.
%
:- pred read_first_item(module_name::in, file_name::in, file_name::out,
module_name::out, message_list::out, item_list::out, maybe(read_term)::out,
module_error::out, io.state::di, io.state::uo) is det.
read_first_item(DefaultModuleName, !SourceFileName, ModuleName,
Messages, Items, MaybeSecondTerm, Error, !IO) :-
globals.io_lookup_bool_option(warn_missing_module_name, WarnMissing, !IO),
globals.io_lookup_bool_option(warn_wrong_module_name, WarnWrong, !IO),
% Parse the first term, treating it as occurring within the scope
% of the special "root" module (so that any `:- module' declaration
% is taken to be a non-nested module unless explicitly qualified).
parser.read_term_filename(!.SourceFileName, MaybeFirstTerm, !IO),
root_module_name(RootModuleName),
process_read_term(RootModuleName, MaybeFirstTerm, MaybeFirstItem),
(
% Apply and then skip `pragma source_file' decls, by calling ourselves
% recursively with the new source file name.
MaybeFirstItem = read_item_ok(FirstItem, _),
FirstItem = item_pragma(_, pragma_source_file(!:SourceFileName))
->
read_first_item(DefaultModuleName, !SourceFileName,
ModuleName, Messages, Items, MaybeSecondTerm, Error, !IO)
;
% Check if the first term was a `:- module' decl.
MaybeFirstItem = read_item_ok(FirstItem, FirstContext),
FirstItem = item_module_defn(_VarSet, ModuleDefn),
ModuleDefn = md_module(StartModuleName)
->
% If so, then check that it matches the expected module name,
% and if not, report a warning.
( match_sym_name(StartModuleName, DefaultModuleName) ->
ModuleName = DefaultModuleName,
Messages = []
; match_sym_name(DefaultModuleName, StartModuleName) ->
ModuleName = StartModuleName,
Messages = []
;
StartModuleNameString = sym_name_to_string(StartModuleName),
WrongModuleWarning = "source file `" ++ !.SourceFileName ++
"' contains module named `" ++ StartModuleNameString ++ "'",
maybe_add_warning(WarnWrong, MaybeFirstTerm, FirstContext,
WrongModuleWarning, [], Messages),
% Which one should we use here? We used to use the default module
% name (computed from the filename) but now we use the declared
% one.
ModuleName = StartModuleName
),
make_module_decl(ModuleName, FirstContext, FixedFirstItem),
Items = [FixedFirstItem],
Error = no_module_errors,
MaybeSecondTerm = no
;
% If the first term was not a `:- module' decl, then issue a warning
% (if warning enabled), and insert an implicit `:- module ModuleName'
% decl.
( MaybeFirstItem = read_item_ok(_FirstItem, FirstContext0) ->
FirstContext = FirstContext0
;
term.context_init(!.SourceFileName, 1, FirstContext)
),
(
WarnMissing = yes,
dummy_term_with_context(FirstContext, FirstTerm),
add_warning("module should start with a `:- module' declaration",
FirstTerm, [], Messages)
;
WarnMissing = no,
Messages = []
),
ModuleName = DefaultModuleName,
make_module_decl(ModuleName, FirstContext, FixedFirstItem),
% Reparse the first term, this time treating it as occuring within
% the scope of the implicit `:- module' decl rather than in the
% root module.
MaybeSecondTerm = yes(MaybeFirstTerm),
Items = [FixedFirstItem],
Error = no_module_errors
).
:- pred make_module_decl(module_name::in, term.context::in,
item_and_context::out) is det.
make_module_decl(ModuleName, Context, item_and_context(Item, Context)) :-
varset.init(EmptyVarSet),
ModuleDefn = md_module(ModuleName),
Item = item_module_defn(EmptyVarSet, ModuleDefn).
:- pred maybe_add_warning(bool::in, read_term::in, term.context::in,
string::in, message_list::in, message_list::out) is det.
maybe_add_warning(DoWarn, MaybeTerm, Context, Warning, !Messages) :-
(
DoWarn = yes,
( MaybeTerm = term(_VarSet, Term) ->
WarningTerm = Term
;
dummy_term_with_context(Context, WarningTerm)
),
add_warning(Warning, WarningTerm, !Messages)
;
DoWarn = no
).
%-----------------------------------------------------------------------------%
% The code below was carefully optimized to run efficiently in NU-Prolog.
% We used to call read_item(MaybeItem) - which does all the work for
% a single item - via io.gc_call/1, which called the goal with
% garbage collection. But optimizing for NU-Prolog is no longer a concern.
:- pred read_items_loop(module_name::in, file_name::in,
message_list::in, message_list::out, item_list::in, item_list::out,
module_error::in, module_error::out, io.state::di, io.state::uo) is det.
read_items_loop(ModuleName, SourceFileName, !Msgs, !Items, !Error, !IO) :-
read_item(ModuleName, SourceFileName, MaybeItem, !IO),
read_items_loop_2(MaybeItem, ModuleName, SourceFileName, !Msgs,
!Items, !Error, !IO).
%-----------------------------------------------------------------------------%
:- pred read_items_loop_2(read_item_result::in, module_name::in,
file_name::in, message_list::in, message_list::out,
item_list::in, item_list::out, module_error::in, module_error::out,
io.state::di, io.state::uo) is det.
read_items_loop_2(MaybeItemOrEOF, !.ModuleName, !.SourceFileName, !Msgs,
!ItemAndContexts, !Error, !IO) :-
(
MaybeItemOrEOF = read_item_eof
% If the next item was end-of-file, then we're done.
;
MaybeItemOrEOF = read_item_syntax_error(ErrorMsg, LineNumber),
% If the next item was a syntax error, then insert it in the list
% of messages and continue looping.
term.context_init(!.SourceFileName, LineNumber, Context),
dummy_term_with_context(Context, Term),
ThisError = ErrorMsg - Term,
!:Msgs = [ThisError | !.Msgs],
!:Error = some_module_errors,
read_items_loop(!.ModuleName, !.SourceFileName, !Msgs,
!ItemAndContexts, !Error, !IO)
;
MaybeItemOrEOF = read_item_errors(Errors),
% If the next item was a semantic error, then insert it in the list
% of messages and continue looping.
list.foldl(add_error, Errors, !Msgs),
!:Error = some_module_errors,
read_items_loop(!.ModuleName, !.SourceFileName, !Msgs,
!ItemAndContexts, !Error, !IO)
;
MaybeItemOrEOF = read_item_ok(Item, Context),
read_items_loop_ok(Item, Context, !ModuleName, !SourceFileName,
!Msgs, !ItemAndContexts, !Error, !IO),
read_items_loop(!.ModuleName, !.SourceFileName, !Msgs,
!ItemAndContexts, !Error, !IO)
).
:- pred read_items_loop_ok(item::in, term.context::in,
module_name::in, module_name::out, file_name::in, file_name::out,
message_list::in, message_list::out,
item_list::in, item_list::out, module_error::in, module_error::out,
io.state::di, io.state::uo) is det.
read_items_loop_ok(Item0, Context, !ModuleName, !SourceFileName, !Msgs,
!ItemAndContexts, !Error, !IO) :-
( Item0 = item_nothing(yes(Warning)) ->
Warning = item_warning(MaybeOption, Msg, Term),
(
MaybeOption = yes(Option),
globals.io_lookup_bool_option(Option, Warn, !IO)
;
MaybeOption = no,
Warn = yes
),
(
Warn = yes,
add_warning(Msg, Term, !Msgs),
globals.io_lookup_bool_option(halt_at_warn, Halt, !IO),
(
Halt = yes,
!:Error = some_module_errors
;
Halt = no
)
;
Warn = no
),
Item = item_nothing(no)
;
Item = Item0
),
% If the next item was a valid item, check whether it was
% a declaration that affects the current parsing context --
% i.e. either a `module'/`end_module' declaration or a
% `pragma source_file' declaration. If so, set the new
% parsing context according. Next, unless the item is a
% `pragma source_file' declaration, insert it into the item list.
% Then continue looping.
( Item = item_pragma(_, pragma_source_file(NewSourceFileName)) ->
!:SourceFileName = NewSourceFileName
; Item = item_module_defn(_VarSet, md_module(NestedModuleName)) ->
!:ModuleName = NestedModuleName,
!:ItemAndContexts = [item_and_context(Item, Context) |
!.ItemAndContexts]
; Item = item_module_defn(_VarSet, md_end_module(NestedModuleName)) ->
root_module_name(RootModuleName),
sym_name_get_module_name(NestedModuleName, RootModuleName,
ParentModuleName),
!:ModuleName = ParentModuleName,
!:ItemAndContexts = [item_and_context(Item, Context) |
!.ItemAndContexts]
; Item = item_module_defn(VarSet, md_import(list_module(Modules))) ->
ImportItems = list.map(make_pseudo_import_module_decl(VarSet, Context),
Modules),
list.append(ImportItems, !ItemAndContexts)
; Item = item_module_defn(VarSet, md_use(list_module(Modules))) ->
UseItems = list.map(make_pseudo_use_module_decl(VarSet, Context),
Modules),
list.append(UseItems, !ItemAndContexts)
; Item = item_module_defn(VarSet, md_include_module(Modules)) ->
IncludeItems = list.map(
make_pseudo_include_module_decl(VarSet, Context),
Modules),
list.append(IncludeItems, !ItemAndContexts)
;
!:ItemAndContexts = [item_and_context(Item, Context) |
!.ItemAndContexts]
).
:- func make_pseudo_import_module_decl(prog_varset, prog_context,
module_specifier) = item_and_context.
make_pseudo_import_module_decl(Varset, Context, ModuleSpecifier) =
item_and_context(
item_module_defn(Varset, md_import(list_module([ModuleSpecifier]))),
Context).
:- func make_pseudo_use_module_decl(prog_varset, prog_context,
module_specifier) = item_and_context.
make_pseudo_use_module_decl(Varset, Context, ModuleSpecifier) =
item_and_context(
item_module_defn(Varset, md_use(list_module([ModuleSpecifier]))),
Context).
:- func make_pseudo_include_module_decl(prog_varset, prog_context, module_name)
= item_and_context.
make_pseudo_include_module_decl(Varset, Context, ModuleSpecifier) =
item_and_context(
item_module_defn(Varset, md_include_module([ModuleSpecifier])),
Context).
%-----------------------------------------------------------------------------%
:- type read_item_result
---> read_item_eof
; read_item_syntax_error(file_name, int)
; read_item_errors(assoc_list(string, term))
; read_item_ok(item, term.context).
% Read_item/1 reads a single item, and if it is a valid term parses it.
%
:- pred read_item(module_name::in, file_name::in, read_item_result::out,
io::di, io::uo) is det.
read_item(ModuleName, SourceFileName, MaybeItem, !IO) :-
parser.read_term_filename(SourceFileName, MaybeTerm, !IO),
process_read_term(ModuleName, MaybeTerm, MaybeItem).
:- pred process_read_term(module_name::in, read_term::in,
read_item_result::out) is det.
process_read_term(_ModuleName, eof, read_item_eof).
process_read_term(_ModuleName, error(ErrorMsg, LineNumber),
read_item_syntax_error(ErrorMsg, LineNumber)).
process_read_term(ModuleName, term(VarSet, Term), MaybeItemOrEof) :-
parse_item(ModuleName, VarSet, Term, MaybeItem),
convert_item(MaybeItem, MaybeItemOrEof).
:- pred convert_item(maybe_item_and_context::in, read_item_result::out) is det.
convert_item(ok2(Item, Context), read_item_ok(Item, Context)).
convert_item(error2(Errors), read_item_errors(Errors)).
parse_item(ModuleName, VarSet, Term, Result) :-
( Term = term.functor(term.atom(":-"), [Decl], _DeclContext) ->
% It's a declaration.
parse_decl(ModuleName, VarSet, Decl, Result)
; Term = term.functor(term.atom("-->"), [DCG_H, DCG_B], DCG_Context) ->
% It's a DCG clause.
parse_dcg_clause(ModuleName, VarSet, DCG_H, DCG_B, DCG_Context, Result)
;
% It's either a fact or a rule.
( Term = term.functor(term.atom(":-"), [H, B], TermContext) ->
% It's a rule.
Head = H,
Body = B,
TheContext = TermContext
;
% It's a fact.
Head = Term,
( Head = term.functor(_Functor, _Args, HeadContext) ->
TheContext = HeadContext
;
% Term consists of just a single variable - the context
% has been lost.
term.context_init(TheContext)
),
Body = term.functor(term.atom("true"), [], TheContext)
),
varset.coerce(VarSet, ProgVarSet),
process_clause(ModuleName, Term, Head, Body, TheContext, ProgVarSet,
Result)
).
:- pred process_clause(module_name::in, term::in, term::in, term::in,
term.context::in, prog_varset::in, maybe_item_and_context::out) is det.
process_clause(ModuleName, Term, Head, Body0, TheContext, ProgVarSet0,
Result) :-
parse_goal(Body0, MaybeBody, ProgVarSet0, ProgVarSet),
(
MaybeBody = ok1(Body),
(
Head = term.functor(term.atom("="), [FuncHead0, FuncResult], _),
FuncHead = desugar_field_access(FuncHead0)
->
parse_implicitly_qualified_term(ModuleName, FuncHead, Head,
"equation head", MaybeFunctor),
process_func_clause(MaybeFunctor, FuncResult, ProgVarSet, Body,
MaybeItem)
;
parse_implicitly_qualified_term(ModuleName, Head, Term,
"clause head", MaybeFunctor),
process_pred_clause(MaybeFunctor, ProgVarSet, Body, MaybeItem)
),
add_context(MaybeItem, TheContext, Result)
;
MaybeBody = error1(Errors),
Result = error2(Errors)
).
:- pred process_pred_clause(maybe_functor::in, prog_varset::in, goal::in,
maybe1(item)::out) is det.
process_pred_clause(ok2(Name, Args0), VarSet, Body,
ok1(item_clause(user, VarSet, pf_predicate, Name, Args, Body))) :-
list.map(term.coerce, Args0, Args).
process_pred_clause(error2(Errors0), _, _, error1(Errors)) :-
Errors = assoc_list.map_values_only(term.coerce, Errors0).
:- pred process_func_clause(maybe_functor::in, term::in, prog_varset::in,
goal::in, maybe1(item)::out) is det.
process_func_clause(ok2(Name, Args0), Result0, VarSet, Body,
ok1(item_clause(user, VarSet, pf_function, Name, Args, Body))) :-
list.append(Args0, [Result0], Args1),
list.map(term.coerce, Args1, Args).
process_func_clause(error2(Errors0), _, _, _, error1(Errors)) :-
Errors = assoc_list.map_values_only(term.coerce, Errors0).
%-----------------------------------------------------------------------------%
:- type decl_attribute
---> decl_attr_purity(purity)
; decl_attr_quantifier(quantifier_type, list(var))
; decl_attr_constraints(quantifier_type, term)
% the term here is the (not yet parsed) list of constraints
; decl_attr_solver_type.
:- type quantifier_type
---> quant_type_exist
; quant_type_univ.
% The term associated with each decl_attribute is the term containing
% both the attribute and the declaration that that attribute modifies;
% this term is used when printing out error messages for cases when
% attributes are used on declarations where they are not allowed.
:- type decl_attrs == assoc_list(decl_attribute, term).
parse_decl(ModuleName, VarSet, F, Result) :-
parse_decl_2(ModuleName, VarSet, F, [], Result).
% parse_decl_2(ModuleName, VarSet, Term, Attributes, Result):
%
% Succeeds if Term is a declaration and binds Result to a representation
% of that declaration. Attributes is a list of enclosing declaration
% attributes, in the order innermost to outermost.
%
:- pred parse_decl_2(module_name::in, varset::in, term::in, decl_attrs::in,
maybe_item_and_context::out) is det.
parse_decl_2(ModuleName, VarSet, F, Attributes, Result) :-
( F = term.functor(term.atom(Atom), Args, Context) ->
( parse_decl_attribute(Atom, Args, Attribute, SubTerm) ->
NewAttributes = [Attribute - F | Attributes],
parse_decl_2(ModuleName, VarSet, SubTerm, NewAttributes, Result)
; process_decl(ModuleName, VarSet, Atom, Args, Attributes, R) ->
add_context(R, Context, Result)
;
Result = error2(["unrecognized declaration" - F])
)
;
Result = error2(["atom expected after `:-'" - F])
).
% process_decl(ModuleName, VarSet, Attributes, Atom, Args, Result):
%
% Succeeds if Atom(Args) is a declaration and binds Result to a
% representation of that declaration. Attributes is a list of
% enclosing declaration attributes, in the order outermost to innermost.
%
:- pred process_decl(module_name::in, varset::in, string::in, list(term)::in,
decl_attrs::in, maybe1(item)::out) is semidet.
process_decl(ModuleName, VarSet, "type", [TypeDecl], Attributes, Result) :-
parse_type_decl(ModuleName, VarSet, TypeDecl, Attributes, Result).
process_decl(ModuleName, VarSet, "pred", [PredDecl], Attributes, Result) :-
parse_type_decl_pred(ModuleName, VarSet, PredDecl, Attributes, Result).
process_decl(ModuleName, VarSet, "func", [FuncDecl], Attributes, Result) :-
parse_type_decl_func(ModuleName, VarSet, FuncDecl, Attributes, Result).
process_decl(ModuleName, VarSet, "mode", [ModeDecl], Attributes, Result) :-
parse_mode_decl(ModuleName, VarSet, ModeDecl, Attributes, Result).
process_decl(ModuleName, VarSet, "inst", [InstDecl], Attributes, Result) :-
parse_inst_decl(ModuleName, VarSet, InstDecl, Result0),
check_no_attributes(Result0, Attributes, Result).
process_decl(_ModuleName, VarSet, "import_module", [ModuleSpec], Attributes,
Result) :-
parse_symlist_decl(parse_module_specifier, make_module, make_import,
ModuleSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_module", [ModuleSpec], Attributes,
Result) :-
parse_symlist_decl(parse_module_specifier, make_module, make_use,
ModuleSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_module", [ModuleSpec], Attributes,
Result) :-
parse_symlist_decl(parse_module_specifier, make_module, make_export,
ModuleSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "import_sym", [SymSpec], Attributes,
Result) :-
parse_symlist_decl(parse_symbol_specifier, make_sym, make_import,
SymSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_sym", [SymSpec], Attributes, Result) :-
parse_symlist_decl(parse_symbol_specifier, make_sym, make_use,
SymSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_sym", [SymSpec], Attributes,
Result) :-
parse_symlist_decl(parse_symbol_specifier, make_sym, make_export,
SymSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "import_pred", [PredSpec], Attributes,
Result) :-
parse_symlist_decl(parse_predicate_specifier, make_pred, make_import,
PredSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_pred", [PredSpec], Attributes,
Result) :-
parse_symlist_decl(parse_predicate_specifier, make_pred, make_use,
PredSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_pred", [PredSpec], Attributes,
Result) :-
parse_symlist_decl(parse_predicate_specifier, make_pred, make_export,
PredSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "import_func", [FuncSpec], Attributes,
Result) :-
parse_symlist_decl(parse_function_specifier, make_func, make_import,
FuncSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_func", [FuncSpec], Attributes,
Result) :-
parse_symlist_decl(parse_function_specifier, make_func, make_use,
FuncSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_func", [FuncSpec], Attributes,
Result) :-
parse_symlist_decl(parse_function_specifier, make_func, make_export,
FuncSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "import_cons", [ConsSpec], Attributes,
Result) :-
parse_symlist_decl(parse_constructor_specifier, make_cons, make_import,
ConsSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_cons", [ConsSpec], Attributes,
Result) :-
parse_symlist_decl(parse_constructor_specifier, make_cons, make_use,
ConsSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_cons", [ConsSpec], Attributes,
Result) :-
parse_symlist_decl(parse_constructor_specifier, make_cons, make_export,
ConsSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "import_type", [TypeSpec], Attributes,
Result) :-
parse_symlist_decl(parse_type_specifier, make_type, make_import,
TypeSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_type", [TypeSpec], Attributes,
Result) :-
parse_symlist_decl(parse_type_specifier, make_type, make_use,
TypeSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_type", [TypeSpec], Attributes,
Result) :-
parse_symlist_decl(parse_type_specifier, make_type, make_export,
TypeSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "import_adt", [ADT_Spec], Attributes,
Result) :-
parse_symlist_decl(parse_adt_specifier, make_adt, make_import,
ADT_Spec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_adt", [ADT_Spec], Attributes, Result) :-
parse_symlist_decl(parse_adt_specifier, make_adt, make_use,
ADT_Spec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_adt", [ADT_Spec], Attributes,
Result) :-
parse_symlist_decl(parse_adt_specifier, make_adt, make_export,
ADT_Spec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "import_op", [OpSpec], Attributes,
Result) :-
parse_symlist_decl(parse_op_specifier, make_op, make_import,
OpSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "use_op", [OpSpec], Attributes, Result) :-
parse_symlist_decl(parse_op_specifier, make_op, make_use,
OpSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet, "export_op", [OpSpec], Attributes, Result) :-
parse_symlist_decl(parse_op_specifier, make_op, make_export,
OpSpec, Attributes, VarSet, Result).
process_decl(_ModuleName, VarSet0, "interface", [], Attributes, Result) :-
varset.coerce(VarSet0, VarSet),
Result0 = ok1(item_module_defn(VarSet, md_interface)),
check_no_attributes(Result0, Attributes, Result).
process_decl(_ModuleName, VarSet0, "implementation", [], Attributes, Result) :-
varset.coerce(VarSet0, VarSet),
Result0 = ok1(item_module_defn(VarSet, md_implementation)),
check_no_attributes(Result0, Attributes, Result).
process_decl(ModuleName, VarSet, "external", Args, Attributes, Result) :-
(
Args = [PredSpec],
MaybeBackend = no
;
Args = [BackendArg, PredSpec],
BackendArg = term.functor(term.atom(Functor), [], _),
(
Functor = "high_level_backend",
Backend = high_level_backend
;
Functor = "low_level_backend",
Backend = low_level_backend
),
MaybeBackend = yes(Backend)
),
parse_implicitly_qualified_symbol_name_specifier(ModuleName,
PredSpec, Result0),
process_maybe1(make_external(VarSet, MaybeBackend), Result0, Result1),
check_no_attributes(Result1, Attributes, Result).
process_decl(DefaultModuleName, VarSet0, "module", [ModuleName], Attributes,
Result) :-
parse_module_name(DefaultModuleName, ModuleName, Result0),
(
Result0 = ok1(ModuleNameSym),
varset.coerce(VarSet0, VarSet),
Result1 = ok1(item_module_defn(VarSet, md_module(ModuleNameSym)))
;
Result0 = error1(Errors),
Result1 = error1(Errors)
),
check_no_attributes(Result1, Attributes, Result).
process_decl(DefaultModuleName, VarSet0, "include_module", [ModuleNames],
Attributes, Result) :-
parse_list(parse_module_name(DefaultModuleName), ModuleNames, Result0),
(
Result0 = ok1(ModuleNameSyms),
varset.coerce(VarSet0, VarSet),
Result1 = ok1(item_module_defn(VarSet,
md_include_module(ModuleNameSyms)))
;
Result0 = error1(Errors),
Result1 = error1(Errors)
),
check_no_attributes(Result1, Attributes, Result).
process_decl(DefaultModuleName, VarSet0, "end_module", [ModuleName],
Attributes, Result) :-
% The name in an `end_module' declaration not inside the scope of the
% module being ended, so the default module name here is the parent
% of the previous default module name.
root_module_name(RootModuleName),
sym_name_get_module_name(DefaultModuleName, RootModuleName,
ParentOfDefaultModuleName),
parse_module_name(ParentOfDefaultModuleName, ModuleName, Result0),
(
Result0 = ok1(ModuleNameSym),
varset.coerce(VarSet0, VarSet),
Result1 = ok1(item_module_defn(VarSet, md_end_module(ModuleNameSym)))
;
Result0 = error1(Errors),
Result1 = error1(Errors)
),
check_no_attributes(Result1, Attributes, Result).
process_decl(ModuleName, VarSet, "pragma", Pragma, Attributes, Result):-
parse_pragma(ModuleName, VarSet, Pragma, Result0),
check_no_attributes(Result0, Attributes, Result).
process_decl(ModuleName, VarSet, "promise", Assertion, Attributes, Result):-
parse_promise(ModuleName, promise_type_true, VarSet,
Assertion, Attributes, Result0),
check_no_attributes(Result0, Attributes, Result).
process_decl(ModuleName, VarSet, "promise_exclusive", PromiseGoal, Attributes,
Result):-
parse_promise(ModuleName, promise_type_exclusive, VarSet,
PromiseGoal, Attributes, Result).
process_decl(ModuleName, VarSet, "promise_exhaustive", PromiseGoal, Attributes,
Result):-
parse_promise(ModuleName, promise_type_exhaustive, VarSet,
PromiseGoal, Attributes, Result).
process_decl(ModuleName, VarSet, "promise_exclusive_exhaustive", PromiseGoal,
Attributes, Result):-
parse_promise(ModuleName, promise_type_exclusive_exhaustive, VarSet,
PromiseGoal, Attributes, Result).
process_decl(ModuleName, VarSet, "typeclass", Args, Attributes, Result):-
parse_typeclass(ModuleName, VarSet, Args, Result0),
check_no_attributes(Result0, Attributes, Result).
process_decl(ModuleName, VarSet, "instance", Args, Attributes, Result):-
parse_instance(ModuleName, VarSet, Args, Result0),
check_no_attributes(Result0, Attributes, Result).
process_decl(ModuleName, VarSet0, "version_numbers",
[VersionNumberTerm, ModuleNameTerm, VersionNumbersTerm],
Attributes, Result) :-
parse_module_specifier(ModuleNameTerm, ModuleNameResult),
(
VersionNumberTerm = term.functor(term.integer(VersionNumber), [], _),
VersionNumber = version_numbers_version_number
->
(
ModuleNameResult = ok1(ModuleName)
->
recompilation.version.parse_version_numbers(VersionNumbersTerm,
Result0),
(
Result0 = ok1(VersionNumbers),
varset.coerce(VarSet0, VarSet),
Result1 = ok1(item_module_defn(VarSet,
md_version_numbers(ModuleName, VersionNumbers))),
check_no_attributes(Result1, Attributes, Result)
;
Result0 = error1(Errors),
Result = error1(Errors)
)
;
Msg = "invalid module name in `:- version_numbers'",
Result = error1([Msg - ModuleNameTerm])
)
;
( VersionNumberTerm = term.functor(_, _, Context) ->
Msg = "interface file needs to be recreated, " ++
"the version numbers are out of date",
dummy_term_with_context(Context, DummyTerm),
Warning = item_warning(yes(warn_smart_recompilation),
Msg, DummyTerm),
Result = ok1(item_nothing(yes(Warning)))
;
Msg = "invalid version number in `:- version_numbers'",
Result = error1([Msg - VersionNumberTerm])
)
).
process_decl(ModuleName, VarSet, InitDecl, Args, Attributes, Result) :-
( InitDecl = "initialise" ; InitDecl = "initialize" ),
parse_initialise_decl(ModuleName, VarSet, Args, Result0),
check_no_attributes(Result0, Attributes, Result).
process_decl(ModuleName, VarSet, FinalDecl, Args, Attributes, Result) :-
( FinalDecl = "finalise" ; FinalDecl = "finalize" ),
parse_finalise_decl(ModuleName, VarSet, Args, Result0),
check_no_attributes(Result0, Attributes, Result).
process_decl(ModuleName, VarSet, "mutable", Args, Attributes, Result) :-
parse_mutable_decl(ModuleName, VarSet, Args, Result0),
check_no_attributes(Result0, Attributes, Result).
:- pred parse_decl_attribute(string::in, list(term)::in, decl_attribute::out,
term::out) is semidet.
parse_decl_attribute("impure", [Decl],
decl_attr_purity(purity_impure), Decl).
parse_decl_attribute("semipure", [Decl],
decl_attr_purity(purity_semipure), Decl).
parse_decl_attribute("<=", [Decl, Constraints],
decl_attr_constraints(quant_type_univ, Constraints), Decl).
parse_decl_attribute("=>", [Decl, Constraints],
decl_attr_constraints(quant_type_exist, Constraints), Decl).
parse_decl_attribute("some", [TVars, Decl],
decl_attr_quantifier(quant_type_exist, TVarsList), Decl) :-
parse_list_of_vars(TVars, TVarsList).
parse_decl_attribute("all", [TVars, Decl],
decl_attr_quantifier(quant_type_univ, TVarsList), Decl) :-
parse_list_of_vars(TVars, TVarsList).
parse_decl_attribute("solver", [Decl], decl_attr_solver_type, Decl).
:- pred check_no_attributes(maybe1(T)::in, decl_attrs::in, maybe1(T)::out)
is det.
check_no_attributes(Result0, Attributes, Result) :-
(
Result0 = ok1(_),
Attributes = [Attr - Term | _]
->
Message = attribute_description(Attr) ++ " not allowed here",
Result = error1([Message - Term])
;
Result = Result0
).
:- func attribute_description(decl_attribute) = string.
attribute_description(decl_attr_purity(_)) = "purity specifier".
attribute_description(decl_attr_quantifier(quant_type_univ, _)) =
"universal quantifier (`all')".
attribute_description(decl_attr_quantifier(quant_type_exist, _)) =
"existential quantifier (`some')".
attribute_description(decl_attr_constraints(quant_type_univ, _)) =
"type class constraint (`<=')".
attribute_description(decl_attr_constraints(quant_type_exist, _)) =
"existentially quantified type class constraint (`=>')".
attribute_description(decl_attr_solver_type) = "solver type specifier".
%-----------------------------------------------------------------------------%
:- pred parse_promise(module_name::in, promise_type::in, varset::in,
list(term)::in, decl_attrs::in, maybe1(item)::out) is semidet.
parse_promise(ModuleName, PromiseType, VarSet, [Term], Attributes, Result) :-
varset.coerce(VarSet, ProgVarSet0),
parse_goal(Term, MaybeGoal0, ProgVarSet0, ProgVarSet),
(
MaybeGoal0 = ok1(Goal0),
% Get universally quantified variables.
(
PromiseType = promise_type_true,
( Goal0 = all_expr(UnivVars0, AllGoal) - _Context ->
UnivVars0 = UnivVars,
Goal = AllGoal
;
UnivVars = [],
Goal = Goal0
)
;
( PromiseType = promise_type_exclusive
; PromiseType = promise_type_exhaustive
; PromiseType = promise_type_exclusive_exhaustive
),
get_quant_vars(quant_type_univ, ModuleName, Attributes, _,
[], UnivVars0),
list.map(term.coerce_var, UnivVars0, UnivVars),
Goal0 = Goal
),
Result = ok1(item_promise(PromiseType, Goal, ProgVarSet, UnivVars))
;
MaybeGoal0 = error1(Errors),
Result = error1(Errors)
).
%-----------------------------------------------------------------------------%
:- pred parse_type_decl(module_name::in, varset::in, term::in, decl_attrs::in,
maybe1(item)::out) is det.
parse_type_decl(ModuleName, VarSet, TypeDecl, Attributes, Result) :-
(
TypeDecl = term.functor(term.atom(Name), Args, _),
parse_type_decl_type(ModuleName, Name, Args, Attributes, Cond, R)
->
R1 = R,
Cond1 = Cond
;
process_abstract_type(ModuleName, TypeDecl, Attributes, R1),
Cond1 = cond_true
),
% We should check the condition for errors (don't bother at the moment,
% since we ignore conditions anyhow :-).
process_maybe1(make_type_defn(VarSet, Cond1), R1, Result).
:- pred make_type_defn(varset::in, condition::in, processed_type_body::in,
item::out) is det.
make_type_defn(VarSet0, Cond, processed_type_body(Name, Args, TypeDefn),
item_type_defn(VarSet, Name, Args, TypeDefn, Cond)) :-
varset.coerce(VarSet0, VarSet).
:- pred make_external(varset::in, maybe(backend)::in, sym_name_specifier::in,
item::out) is det.
make_external(VarSet0, MaybeBackend, SymSpec,
item_module_defn(VarSet, md_external(MaybeBackend, SymSpec))) :-
varset.coerce(VarSet0, VarSet).
:- pred get_is_solver_type(is_solver_type::out,
decl_attrs::in, decl_attrs::out) is det.
get_is_solver_type(IsSolverType, !Attributes) :-
( !.Attributes = [decl_attr_solver_type - _ | !:Attributes] ->
IsSolverType = solver_type
;
IsSolverType = non_solver_type
).
%-----------------------------------------------------------------------------%
% Add a warning message to the list of messages.
%
:- pred add_warning(string::in, term::in, message_list::in, message_list::out)
is det.
add_warning(Warning, Term, Msgs, [Msg - Term | Msgs]) :-
string.append("Warning: ", Warning, Msg).
% Add an error message to the list of messages.
%
:- pred add_error(pair(string, term)::in, message_list::in, message_list::out)
is det.
add_error(BaseMsg - Term, Msgs, [Msg - Term | Msgs]) :-
string.append("Error: ", BaseMsg, Msg).
%-----------------------------------------------------------------------------%
% parse_type_decl_type(Term, Condition, Result) succeeds if Term is
% a "type" type declaration, and binds Condition to the condition for
% that declaration (if any), and Result to a representation of the
% declaration.
%
:- pred parse_type_decl_type(module_name::in, string::in, list(term)::in,
decl_attrs::in, condition::out, maybe1(processed_type_body)::out)
is semidet.
parse_type_decl_type(ModuleName, "--->", [HeadTerm, BodyTerm], Attributes0,
Condition, Result) :-
get_condition(BodyTerm, Body, Condition),
get_is_solver_type(IsSolverType, Attributes0, Attributes),
(
IsSolverType = solver_type,
Msg = "a solver type cannot have data constructors",
Result = error1([Msg - HeadTerm])
;
IsSolverType = non_solver_type,
du_type_rhs_ctors_and_where_terms(Body, CtorsTerm, MaybeWhereTerm),
CtorsResult = convert_constructors(ModuleName, CtorsTerm),
(
CtorsResult = error1(Errors),
Result = error1(Errors)
;
CtorsResult = ok1(Ctors),
WhereResult = parse_type_decl_where_term(non_solver_type,
ModuleName, MaybeWhereTerm),
(
WhereResult = error2(Errors),
Result = error1(Errors)
;
% The code to process `where' attributes will return an error
% result if solver attributes are given for a non-solver type.
% Because this is a du type, if the unification with
% WhereResult succeeds then _NoSolverTypeDetails is
% guaranteed to be `no'.
WhereResult = ok2(_NoSolverTypeDetails, MaybeUserEqComp),
process_du_type(ModuleName, HeadTerm, Body, Ctors,
MaybeUserEqComp, Result0),
check_no_attributes(Result0, Attributes, Result)
)
)
).
parse_type_decl_type(ModuleName, "==", [HeadTerm, BodyTerm], Attributes,
Condition, Result) :-
get_condition(BodyTerm, Body, Condition),
process_eqv_type(ModuleName, HeadTerm, Body, Result0),
check_no_attributes(Result0, Attributes, Result).
parse_type_decl_type(ModuleName, "where", [HeadTerm, BodyTerm], Attributes0,
Condition, Result) :-
get_condition(BodyTerm, Body, Condition),
get_is_solver_type(IsSolverType, Attributes0, Attributes),
(
IsSolverType = non_solver_type,
Msg = "only solver types can be defined by a `where' block alone",
Result = error1([Msg - HeadTerm])
;
IsSolverType = solver_type,
Result0 = parse_type_decl_where_term(solver_type, ModuleName,
yes(Body)),
(
Result0 = error2(Errors),
Result = error1(Errors)
;
Result0 = ok2(MaybeSolverTypeDetails, MaybeUserEqComp),
process_solver_type(ModuleName, HeadTerm,
MaybeSolverTypeDetails, MaybeUserEqComp, Result1),
check_no_attributes(Result1, Attributes, Result)
)
).
:- pred du_type_rhs_ctors_and_where_terms(term::in,
term::out, maybe(term)::out) is det.
du_type_rhs_ctors_and_where_terms(Term, CtorsTerm, MaybeWhereTerm) :-
(
Term = term.functor(term.atom("where"), [CtorsTerm0, WhereTerm],
_Context)
->
CtorsTerm = CtorsTerm0,
MaybeWhereTerm = yes(WhereTerm)
;
CtorsTerm = Term,
MaybeWhereTerm = no
).
%-----------------------------------------------------------------------------%
% parse_type_decl_pred(ModuleName, VarSet, Pred, Attributes, Result)
% succeeds if Pred is a predicate type declaration, and binds Result
% to a representation of the declaration.
%
:- pred parse_type_decl_pred(module_name::in, varset::in, term::in,
decl_attrs::in, maybe1(item)::out) is det.
parse_type_decl_pred(ModuleName, VarSet, Pred, Attributes, Result) :-
get_condition(Pred, Body, Condition),
get_determinism(Body, Body2, MaybeDeterminism),
get_with_inst(Body2, Body3, WithInst),
get_with_type(Body3, Body4, WithTypeResult),
( WithTypeResult = ok1(WithType),
process_type_decl_pred_or_func(pf_predicate, ModuleName, WithType,
WithInst, MaybeDeterminism, VarSet, Body4, Condition, Attributes,
Result)
;
WithTypeResult = error1(Errors),
Result = error1(Errors)
).
:- pred process_type_decl_pred_or_func(pred_or_func::in, module_name::in,
maybe(mer_type)::in, maybe1(maybe(mer_inst))::in,
maybe1(maybe(determinism))::in, varset::in, term::in, condition::in,
decl_attrs::in, maybe1(item)::out) is det.
process_type_decl_pred_or_func(PredOrFunc, ModuleName, WithType, WithInst0,
MaybeDeterminism0, VarSet, Body, Condition, Attributes, Result) :-
(
MaybeDeterminism0 = ok1(MaybeDeterminism),
(
WithInst0 = ok1(WithInst),
( MaybeDeterminism = yes(_), WithInst = yes(_) ->
Msg = "`with_inst` and determinism both specified",
Result = error1([Msg - Body])
; WithInst = yes(_), WithType = no ->
Msg = "`with_inst` specified without `with_type`",
Result = error1([Msg - Body])
;
(
% Function declarations with `with_type` annotations
% have the same form as predicate declarations.
PredOrFunc = pf_function,
WithType = no
->
process_func(ModuleName, VarSet, Body, Condition,
MaybeDeterminism, Attributes, Result)
;
process_pred_or_func(PredOrFunc, ModuleName, VarSet, Body,
Condition, WithType, WithInst, MaybeDeterminism,
Attributes, Result)
)
)
;
WithInst0 = error1(Errors),
Result = error1(Errors)
)
;
MaybeDeterminism0 = error1(Errors),
Result = error1(Errors)
).
%-----------------------------------------------------------------------------%
% parse_type_decl_func(ModuleName, Varset, Func, Attributes, Result)
% succeeds if Func is a function type declaration, and binds Result to
% a representation of the declaration.
%
:- pred parse_type_decl_func(module_name::in, varset::in, term::in,
decl_attrs::in, maybe1(item)::out) is det.
parse_type_decl_func(ModuleName, VarSet, Func, Attributes, Result) :-
get_condition(Func, Body, Condition),
get_determinism(Body, Body2, MaybeDeterminism),
get_with_inst(Body2, Body3, WithInst),
get_with_type(Body3, Body4, WithTypeResult),
(
WithTypeResult = ok1(WithType),
process_type_decl_pred_or_func(pf_function, ModuleName,
WithType, WithInst, MaybeDeterminism, VarSet, Body4,
Condition, Attributes, Result)
;
WithTypeResult = error1(Errors),
Result = error1(Errors)
).
%-----------------------------------------------------------------------------%
% parse_mode_decl_pred(ModuleName, Pred, Condition, Result) succeeds
% if Pred is a predicate mode declaration, and binds Condition to the
% condition for that declaration (if any), and Result to a
% representation of the declaration.
%
:- pred parse_mode_decl_pred(module_name::in, varset::in, term::in,
decl_attrs::in, maybe1(item)::out) is det.
parse_mode_decl_pred(ModuleName, VarSet, Pred, Attributes, Result) :-
get_condition(Pred, Body, Condition),
get_determinism(Body, Body2, MaybeDeterminism0),
get_with_inst(Body2, Body3, WithInst0),
(
MaybeDeterminism0 = ok1(MaybeDeterminism),
(
WithInst0 = ok1(WithInst),
(
MaybeDeterminism = yes(_),
WithInst = yes(_)
->
Msg = "`with_inst` and determinism both specified",
Result = error1([Msg - Body])
;
process_mode(ModuleName, VarSet, Body3, Condition, Attributes,
WithInst, MaybeDeterminism, Result)
)
;
WithInst0 = error1(Errors),
Result = error1(Errors)
)
;
MaybeDeterminism0 = error1(Errors),
Result = error1(Errors)
).
%-----------------------------------------------------------------------------%
:- pred parse_initialise_decl(module_name::in, varset::in, list(term)::in,
maybe1(item)::out) is semidet.
parse_initialise_decl(_ModuleName, _VarSet, [Term], Result) :-
parse_symbol_name_specifier(Term, MaybeSymNameSpecifier),
(
MaybeSymNameSpecifier = error1(Errors),
Result = error1(Errors)
;
MaybeSymNameSpecifier = ok1(SymNameSpecifier),
(
SymNameSpecifier = name(_),
Result = error1(["`initialise' declaration requires arity" - Term])
;
SymNameSpecifier = name_arity(SymName, Arity),
(
( Arity = 0 ; Arity = 2 )
->
Result = ok1(item_initialise(user, SymName, Arity))
;
Msg = "`initialise' declaration specifies a predicate " ++
"whose arity is not zero or two",
Result = error1([Msg - Term])
)
)
).
%-----------------------------------------------------------------------------%
:- pred parse_finalise_decl(module_name::in, varset::in, list(term)::in,
maybe1(item)::out) is semidet.
parse_finalise_decl(_ModuleName, _VarSet, [Term], Result) :-
parse_symbol_name_specifier(Term, MaybeSymNameSpecifier),
(
MaybeSymNameSpecifier = error1(Errors),
Result = error1(Errors)
;
MaybeSymNameSpecifier = ok1(SymNameSpecifier),
(
SymNameSpecifier = name(_),
Result = error1(["`finalise' declaration requires arity" - Term])
;
SymNameSpecifier = name_arity(SymName, Arity),
(
( Arity = 0 ; Arity = 2 )
->
Result = ok1(item_finalise(user, SymName, Arity))
;
Msg = "`finalise' declaration specifies a predicate " ++
"whose arity is not zero or two",
Result = error1([Msg - Term])
)
)
).
%-----------------------------------------------------------------------------%
%
% Mutable declarations
%
% See prog_mutable.m for implementation details.
%
:- pred parse_mutable_decl(module_name::in, varset::in, list(term)::in,
maybe1(item)::out) is semidet.
parse_mutable_decl(_ModuleName, Varset, Terms, Result) :-
Terms = [NameTerm, TypeTerm, ValueTerm, InstTerm | OptMutAttrsTerm],
parse_mutable_name(NameTerm, NameResult),
parse_mutable_type(TypeTerm, TypeResult),
term.coerce(ValueTerm, Value),
varset.coerce(Varset, ProgVarset),
parse_mutable_inst(InstTerm, InstResult),
%
% The list of attributes is optional.
%
(
OptMutAttrsTerm = [],
MutAttrsResult = ok1(default_mutable_attributes)
;
OptMutAttrsTerm = [MutAttrsTerm],
parse_mutable_attrs(MutAttrsTerm, MutAttrsResult)
),
(
NameResult = ok1(Name),
TypeResult = ok1(Type),
InstResult = ok1(Inst),
MutAttrsResult = ok1(MutAttrs)
->
% We *must* attach the varset to the mutable item because if the
% initial value is non-ground, then the initial value will be a
% variable and the mutable initialisation predicate will contain
% references to it. Ignoring the varset may lead to later compiler
% passes attempting to reuse this variable when fresh variables are
% allocated.
Result = ok1(item_mutable(Name, Type, Value, Inst, MutAttrs,
ProgVarset))
;
Errors = get_any_errors1(NameResult) ++ get_any_errors1(TypeResult) ++
get_any_errors1(InstResult) ++ get_any_errors1(MutAttrsResult),
Result = error1(Errors)
).
:- pred parse_mutable_name(term::in, maybe1(string)::out) is det.
parse_mutable_name(NameTerm, NameResult) :-
( NameTerm = term.functor(atom(Name), [], _) ->
NameResult = ok1(Name)
;
NameResult = error1(["invalid mutable name" - NameTerm])
).
:- pred parse_mutable_type(term::in, maybe1(mer_type)::out) is det.
parse_mutable_type(TypeTerm, TypeResult) :-
( term.contains_var(TypeTerm, _) ->
Msg = "the type in a mutable declaration cannot contain variables",
TypeResult = error1([Msg - TypeTerm])
;
parse_type(TypeTerm, TypeResult)
).
:- pred parse_mutable_inst(term::in, maybe1(mer_inst)::out) is det.
parse_mutable_inst(InstTerm, InstResult) :-
( term.contains_var(InstTerm, _) ->
Msg = "the inst in a mutable declaration cannot contain variables",
InstResult = error1([Msg - InstTerm])
; convert_inst(no_allow_constrained_inst_var, InstTerm, Inst) ->
InstResult = ok1(Inst)
;
InstResult = error1(["invalid inst in mutable declaration" - InstTerm])
).
:- type collected_mutable_attribute
---> mutable_attr_trailed(mutable_trailed)
; mutable_attr_foreign_name(foreign_name)
; mutable_attr_attach_to_io_state(bool)
; mutable_attr_constant(bool)
; mutable_attr_thread_local(mutable_thread_local).
:- pred parse_mutable_attrs(term::in,
maybe1(mutable_var_attributes)::out) is det.
parse_mutable_attrs(MutAttrsTerm, MutAttrsResult) :-
Attributes0 = default_mutable_attributes,
ConflictingAttributes = [
mutable_attr_trailed(mutable_trailed) -
mutable_attr_trailed(mutable_untrailed),
mutable_attr_trailed(mutable_trailed) -
mutable_attr_thread_local(mutable_thread_local),
mutable_attr_constant(yes) - mutable_attr_trailed(mutable_trailed),
mutable_attr_constant(yes) - mutable_attr_attach_to_io_state(yes),
mutable_attr_constant(yes) -
mutable_attr_thread_local(mutable_thread_local)
],
(
list_term_to_term_list(MutAttrsTerm, MutAttrTerms),
map_parser(parse_mutable_attr, MutAttrTerms, MaybeAttrList),
MaybeAttrList = ok1(CollectedMutAttrs)
->
% We check for trailed/untrailed, constant/trailed,
% trailed/thread_local, constant/attach_to_io_state,
% constant/thread_local conflicts here and deal with conflicting
% foreign_name attributes in make_hlds_passes.m.
%
(
list.member(Conflict1 - Conflict2, ConflictingAttributes),
list.member(Conflict1, CollectedMutAttrs),
list.member(Conflict2, CollectedMutAttrs)
->
Msg = "conflicting attributes in attribute list",
MutAttrsResult = error1([Msg - MutAttrsTerm])
;
list.foldl(process_mutable_attribute, CollectedMutAttrs,
Attributes0, Attributes),
MutAttrsResult = ok1(Attributes)
)
;
Msg = "malformed attribute list in mutable declaration",
MutAttrsResult = error1([Msg - MutAttrsTerm])
).
:- pred process_mutable_attribute(collected_mutable_attribute::in,
mutable_var_attributes::in, mutable_var_attributes::out) is det.
process_mutable_attribute(mutable_attr_trailed(Trailed), !Attributes) :-
set_mutable_var_trailed(Trailed, !Attributes).
process_mutable_attribute(mutable_attr_foreign_name(ForeignName),
!Attributes) :-
set_mutable_add_foreign_name(ForeignName, !Attributes).
process_mutable_attribute(mutable_attr_attach_to_io_state(AttachToIOState),
!Attributes) :-
set_mutable_var_attach_to_io_state(AttachToIOState, !Attributes).
process_mutable_attribute(mutable_attr_constant(Constant), !Attributes) :-
set_mutable_var_constant(Constant, !Attributes),
(
Constant = yes,
set_mutable_var_trailed(mutable_untrailed, !Attributes),
set_mutable_var_attach_to_io_state(no, !Attributes)
;
Constant = no
).
process_mutable_attribute(mutable_attr_thread_local(ThrLocal), !Attributes) :-
set_mutable_var_thread_local(ThrLocal, !Attributes).
:- pred parse_mutable_attr(term::in,
maybe1(collected_mutable_attribute)::out) is det.
parse_mutable_attr(MutAttrTerm, MutAttrResult) :-
(
MutAttrTerm = term.functor(term.atom(String), [], _),
(
String = "untrailed",
MutAttr = mutable_attr_trailed(mutable_untrailed)
;
String = "trailed",
MutAttr = mutable_attr_trailed(mutable_trailed)
;
String = "attach_to_io_state",
MutAttr = mutable_attr_attach_to_io_state(yes)
;
String = "constant",
MutAttr = mutable_attr_constant(yes)
;
String = "thread_local",
MutAttr = mutable_attr_thread_local(mutable_thread_local)
)
->
MutAttrResult = ok1(MutAttr)
;
MutAttrTerm = term.functor(term.atom("foreign_name"), Args, _),
Args = [LangTerm, ForeignNameTerm],
parse_foreign_language(LangTerm, Lang),
ForeignNameTerm = term.functor(term.string(ForeignName), [], _)
->
MutAttr = mutable_attr_foreign_name(foreign_name(Lang, ForeignName)),
MutAttrResult = ok1(MutAttr)
;
Msg = "unrecognised attribute in mutable declaration",
MutAttrResult = error1([Msg - MutAttrTerm])
).
%-----------------------------------------------------------------------------%
% The optional `where ...' part of the type definition syntax
% is a comma separated list of special type `attributes'.
%
% The possible attributes (in this order) are either
% - `type_is_abstract_noncanonical' on its own appears only in .int2
% files and indicates that the type has user-defined equality and/or
% comparison, but that what these predicates are is not known at
% this point
% or
% - `representation is <<type name>>' (required for solver types)
% - `initialisation is <<pred name>>' (required for solver types)
% - `ground is <<inst>>' (required for solver types)
% - `any is <<inst>>' (required for solver types)
% - `equality is <<pred name>>' (optional)
% - `comparison is <<pred name>>' (optional).
%
parse_type_decl_where_part_if_present(IsSolverType, ModuleName, Term0, Term,
Result) :-
(
Term0 = term.functor(term.atom("where"), [Term1, WhereTerm],
_Context)
->
Term = Term1,
Result = parse_type_decl_where_term(IsSolverType, ModuleName,
yes(WhereTerm))
;
Term = Term0,
Result = ok2(no, no)
).
% The maybe2 wrapper allows us to return an error code or a pair
% of results. Either result half may be empty, hence the maybe
% wrapper around each of those.
%
:- func parse_type_decl_where_term(is_solver_type, module_name, maybe(term)) =
maybe2(maybe(solver_type_details), maybe(unify_compare)).
parse_type_decl_where_term(_IsSolverType, _ModuleName, no) =
ok2(no, no).
parse_type_decl_where_term(IsSolverType, ModuleName, MaybeTerm0 @ yes(Term)) =
MaybeWhereDetails :-
some [!MaybeTerm] (
!:MaybeTerm = MaybeTerm0,
parse_where_attribute(parse_where_type_is_abstract_noncanonical,
TypeIsAbstractNoncanonicalResult, !MaybeTerm),
parse_where_attribute(parse_where_is("representation",
parse_where_type_is(ModuleName)),
RepresentationIsResult, !MaybeTerm),
parse_where_attribute(parse_where_initialisation_is(ModuleName),
InitialisationIsResult, !MaybeTerm),
parse_where_attribute(parse_where_is("ground",
parse_where_inst_is(ModuleName)),
GroundIsResult, !MaybeTerm),
parse_where_attribute(parse_where_is("any",
parse_where_inst_is(ModuleName)),
AnyIsResult, !MaybeTerm),
parse_where_attribute(parse_where_is("constraint_store",
parse_where_mutable_is(ModuleName)),
CStoreIsResult, !MaybeTerm),
parse_where_attribute(parse_where_is("equality",
parse_where_pred_is(ModuleName)),
EqualityIsResult, !MaybeTerm),
parse_where_attribute(parse_where_is("comparison",
parse_where_pred_is(ModuleName)),
ComparisonIsResult, !MaybeTerm),
parse_where_end(!.MaybeTerm, WhereEndResult)
),
MaybeWhereDetails =
make_maybe_where_details(
IsSolverType,
TypeIsAbstractNoncanonicalResult,
RepresentationIsResult,
InitialisationIsResult,
GroundIsResult,
AnyIsResult,
CStoreIsResult,
EqualityIsResult,
ComparisonIsResult,
WhereEndResult,
Term
).
% parse_where_attribute(Parser, Result, MaybeTerm0, MaybeTerm)
% handles
% - where MaybeTerm0 may contain nothing
% - where MaybeTerm0 may be a comma-separated pair
% - applies Parser to the appropriate (sub)term to obtain Result
% - sets MaybeTerm depending upon whether the Result is an error
% or not and whether there is more to parse because MaybeTerm0
% was a comma-separated pair.
%
:- pred parse_where_attribute((func(term) = maybe1(maybe(T)))::in,
maybe1(maybe(T))::out, maybe(term)::in, maybe(term)::out) is det.
parse_where_attribute(_Parser, ok1(no), no, no).
parse_where_attribute( Parser, Result, yes(Term0), MaybeRest) :-
(
Term0 = term.functor(term.atom(","), [Term1, Term], _Context)
->
Result = Parser(Term1),
MaybeRestIfYes = yes(Term)
;
Result = Parser(Term0),
MaybeRestIfYes = no
),
(
Result = error1(_),
MaybeRest = no
;
Result = ok1(no),
MaybeRest = yes(Term0)
;
Result = ok1(yes(_)),
MaybeRest = MaybeRestIfYes
).
% Parser for `where ...' attributes of the form
% `attributename is attributevalue'.
%
:- func parse_where_is(string, func(term) = maybe1(T), term) =
maybe1(maybe(T)).
parse_where_is(Name, Parser, Term) = Result :-
( Term = term.functor(term.atom("is"), [LHS, RHS], _Context1) ->
( LHS = term.functor(term.atom(Name), [], _Context2) ->
RHSResult = Parser(RHS),
(
RHSResult = ok1(ParsedRHS),
Result = ok1(yes(ParsedRHS))
;
RHSResult = error1(Errors),
Result = error1(Errors)
)
;
Result = ok1(no)
)
;
Result = error1(["expected is/2" - Term])
).
:- func parse_where_type_is_abstract_noncanonical(term) = maybe1(maybe(unit)).
parse_where_type_is_abstract_noncanonical(Term) =
(
Term = term.functor(term.atom("type_is_abstract_noncanonical"), [],
_Context)
->
ok1(yes(unit))
;
ok1(no)
).
:- func parse_where_initialisation_is(module_name, term) =
maybe1(maybe(sym_name)).
parse_where_initialisation_is(ModuleName, Term) = Result :-
Result0 = parse_where_is("initialisation", parse_where_pred_is(ModuleName),
Term),
(
Result0 = ok1(no)
->
Result1 = parse_where_is("initialization",
parse_where_pred_is(ModuleName), Term)
;
Result1 = Result0
),
promise_pure (
(
Result1 = ok1(yes(_)),
semipure semipure_get_solver_auto_init_supported(AutoInitSupported),
(
AutoInitSupported = yes,
Result = Result1
;
AutoInitSupported = no,
Msg = "unknown attribute in solver type definition",
Result = error1([Msg - Term])
)
;
( Result1 = ok1(no)
; Result1 = error1(_)
),
Result = Result1
)
).
:- func parse_where_pred_is(module_name, term) = maybe1(sym_name).
parse_where_pred_is(ModuleName, Term) = Result :-
parse_implicitly_qualified_symbol_name(ModuleName, Term, Result).
:- func parse_where_inst_is(module_name, term) = maybe1(mer_inst).
parse_where_inst_is(_ModuleName, Term) =
(
prog_io_util.convert_inst(no_allow_constrained_inst_var, Term, Inst),
not prog_mode.inst_contains_unconstrained_var(Inst)
->
ok1(Inst)
;
error1(["expected a ground, unconstrained inst" - Term])
).
:- func parse_where_type_is(module_name, term) = maybe1(mer_type).
parse_where_type_is(_ModuleName, Term) = Result :-
prog_io_util.parse_type(Term, Result).
:- func parse_where_mutable_is(module_name, term) = maybe1(list(item)).
parse_where_mutable_is(ModuleName, Term) = Result :-
( Term = term.functor(term.atom("mutable"), _Args, _Ctxt) ->
parse_mutable_decl_term(ModuleName, Term, Result0),
(
Result0 = ok1(Mutable),
Result = ok1([Mutable])
;
Result0 = error1(Errors),
Result = error1(Errors)
)
; list_term_to_term_list(Term, Terms) ->
map_parser(parse_mutable_decl_term(ModuleName), Terms, Result)
;
Msg = "expected a mutable declaration or a list of " ++
"mutable declarations",
Result = error1([Msg - Term])
).
:- pred parse_mutable_decl_term(module_name::in, term::in, maybe1(item)::out)
is det.
parse_mutable_decl_term(ModuleName, Term, Result) :-
(
Term = term.functor(term.atom("mutable"), Args, _Ctxt),
varset.init(VarSet),
parse_mutable_decl(ModuleName, VarSet, Args, Result0)
->
Result = Result0
;
Result = error1(["expected a mutable declaration" - Term])
).
:- pred parse_where_end(maybe(term)::in, maybe1(maybe(unit))::out) is det.
parse_where_end(no, ok1(yes(unit))).
parse_where_end(yes(Term), error1([Msg - Term])) :-
Msg = "attributes are either badly ordered or " ++
"contain an unrecognised attribute".
:- func make_maybe_where_details(is_solver_type, maybe1(maybe(unit)),
maybe1(maybe(mer_type)), maybe1(maybe(init_pred)),
maybe1(maybe(mer_inst)), maybe1(maybe(mer_inst)),
maybe1(maybe(list(item))),
maybe1(maybe(equality_pred)), maybe1(maybe(comparison_pred)),
maybe1(maybe(unit)), term)
= maybe2(maybe(solver_type_details), maybe(unify_compare)).
make_maybe_where_details(IsSolverType, TypeIsAbstractNoncanonicalResult,
RepresentationIsResult, InitialisationIsResult,
GroundIsResult, AnyIsResult, CStoreIsResult,
EqualityIsResult, ComparisonIsResult, WhereEndResult, WhereTerm)
= Result :-
(
TypeIsAbstractNoncanonicalResult = ok1(TypeIsAbstractNoncanonical),
RepresentationIsResult = ok1(RepresentationIs),
InitialisationIsResult = ok1(InitialisationIs),
GroundIsResult = ok1(GroundIs),
AnyIsResult = ok1(AnyIs),
CStoreIsResult = ok1(CStoreIs),
EqualityIsResult = ok1(EqualityIs),
ComparisonIsResult = ok1(ComparisonIs),
WhereEndResult = ok1(WhereEnd)
->
Result = make_maybe_where_details_2(IsSolverType,
TypeIsAbstractNoncanonical, RepresentationIs, InitialisationIs,
GroundIs, AnyIs, CStoreIs, EqualityIs, ComparisonIs,
WhereEnd, WhereTerm)
;
TypeIsAbstractNoncanonicalErrors =
get_any_errors1(TypeIsAbstractNoncanonicalResult),
RepresentationIsErrors = get_any_errors1(RepresentationIsResult),
InitialisationIsErrors = get_any_errors1(InitialisationIsResult),
GroundIsErrors = get_any_errors1(GroundIsResult),
AnyIsErrors = get_any_errors1(AnyIsResult),
CStoreIsErrors = get_any_errors1(CStoreIsResult),
EqualityIsErrors = get_any_errors1(EqualityIsResult),
ComparisonIsErrors = get_any_errors1(ComparisonIsResult),
WhereEndErrors = get_any_errors1(WhereEndResult),
Errors = TypeIsAbstractNoncanonicalErrors ++ RepresentationIsErrors ++
InitialisationIsErrors ++ GroundIsErrors ++ AnyIsErrors ++
CStoreIsErrors ++ EqualityIsErrors ++ ComparisonIsErrors ++
WhereEndErrors,
Result = error2(Errors)
).
:- func make_maybe_where_details_2(is_solver_type, maybe(unit),
maybe(mer_type), maybe(init_pred), maybe(mer_inst), maybe(mer_inst),
maybe(list(item)), maybe(equality_pred), maybe(comparison_pred),
maybe(unit), term)
= maybe2(maybe(solver_type_details), maybe(unify_compare)).
make_maybe_where_details_2(IsSolverType, TypeIsAbstractNoncanonical,
RepresentationIs, InitialisationIs, GroundIs, AnyIs, CStoreIs,
EqualityIs, ComparisonIs, _WhereEnd, WhereTerm) = Result :-
(
TypeIsAbstractNoncanonical = yes(_),
% rafe: XXX I think this is wrong. There isn't a problem with having
% the solver_type_details and type_is_abstract_noncanonical.
(
RepresentationIs = maybe.no,
InitialisationIs = maybe.no,
GroundIs = maybe.no,
AnyIs = maybe.no,
EqualityIs = maybe.no,
ComparisonIs = maybe.no,
CStoreIs = maybe.no
->
Result = ok2(no, yes(abstract_noncanonical_type(IsSolverType)))
;
Msg = "`where type_is_abstract_noncanonical' "
++ " excludes other `where ...' attributes",
Result = error2([Msg - WhereTerm])
)
;
TypeIsAbstractNoncanonical = maybe.no,
(
IsSolverType = solver_type,
(
RepresentationIs = yes(RepnType),
InitialisationIs = MaybeInitialisation,
GroundIs = MaybeGroundInst,
AnyIs = MaybeAnyInst,
EqualityIs = MaybeEqPred,
ComparisonIs = MaybeCmpPred,
CStoreIs = MaybeMutableItems
->
(
MaybeGroundInst = yes(GroundInst)
;
MaybeGroundInst = no,
GroundInst = ground_inst
),
(
MaybeAnyInst = yes(AnyInst)
;
MaybeAnyInst = no,
AnyInst = ground_inst
),
(
MaybeMutableItems = yes(MutableItems)
;
MaybeMutableItems = no,
MutableItems = []
),
(
MaybeInitialisation = yes(InitPred),
HowToInit = solver_init_automatic(InitPred)
;
MaybeInitialisation = no,
HowToInit = solver_init_explicit
),
SolverTypeDetails = solver_type_details(
RepnType, HowToInit, GroundInst, AnyInst, MutableItems),
MaybeSolverTypeDetails = yes(SolverTypeDetails),
(
MaybeEqPred = no,
MaybeCmpPred = no
->
MaybeUnifyCompare = no
;
MaybeUnifyCompare = yes(unify_compare(
MaybeEqPred, MaybeCmpPred))
),
Result = ok2(MaybeSolverTypeDetails, MaybeUnifyCompare)
;
RepresentationIs = no
->
Msg = "solver type definitions must have a" ++
"`representation' attribute",
Result = error2([Msg - WhereTerm])
;
unexpected(this_file, "make_maybe_where_details_2: " ++
"shouldn't have reached this point! (1)")
)
;
IsSolverType = non_solver_type,
(
( RepresentationIs = yes(_)
; InitialisationIs = yes(_)
; GroundIs = yes(_)
; AnyIs = yes(_)
; CStoreIs = yes(_)
)
->
Msg = "solver type attribute given for non-solver type",
Result = error2([Msg - WhereTerm])
;
EqualityIs = MaybeEqPred,
ComparisonIs = MaybeCmpPred,
Result = ok2(no, yes(unify_compare(MaybeEqPred, MaybeCmpPred)))
)
)
).
% get_determinism(Term0, Term, Determinism) binds Determinism
% to a representation of the determinism condition of Term0, if any,
% and binds Term to the other part of Term0. If Term0 does not
% contain a determinism, then Determinism is bound to `unspecified'.
%
:- pred get_determinism(term::in, term::out, maybe1(maybe(determinism))::out)
is det.
get_determinism(Body0, Body, Determinism) :-
(
Body0 = term.functor(term.atom("is"), Args, _Context1),
Args = [Body1, Determinism1]
->
Body = Body1,
(
Determinism1 = term.functor(term.atom(Determinism2), [],
_Context2),
standard_det(Determinism2, Determinism3)
->
Determinism = ok1(yes(Determinism3))
;
Determinism = error1(["invalid category" - Determinism1])
)
;
Body = Body0,
Determinism = ok1(no)
).
% Process the `with_inst` part of a declaration of the form:
% :- mode p(int) `with_inst` (pred(in, out) is det).
%
:- pred get_with_inst(term::in, term::out, maybe1(maybe(mer_inst))::out)
is det.
get_with_inst(Body0, Body, WithInst) :-
(
Body0 = term.functor(term.atom("with_inst"), [Body1, Inst1], _)
->
( convert_inst(allow_constrained_inst_var, Inst1, Inst) ->
WithInst = ok1(yes(Inst))
;
WithInst = error1(["invalid inst in `with_inst`" - Body0])
),
Body = Body1
;
Body = Body0,
WithInst = ok1(no)
).
:- pred get_with_type(term::in, term::out, maybe1(maybe(mer_type))::out)
is det.
get_with_type(Body0, Body, Result) :-
(
Body0 = term.functor(TypeQualifier, [Body1, Type1], _),
(
TypeQualifier = term.atom("with_type")
;
TypeQualifier = term.atom(":")
)
->
Body = Body1,
parse_type(Type1, Result0),
(
Result0 = ok1(Type),
Result = ok1(yes(Type))
;
Result0 = error1(Errors),
Result = error1(Errors)
)
;
Body = Body0,
Result = ok1(no)
).
%-----------------------------------------------------------------------------%
% get_condition(Term0, Term, Condition) binds Condition
% to a representation of the 'where' condition of Term0, if any,
% and binds Term to the other part of Term0. If Term0 does not
% contain a condition, then Condition is bound to true.
%
:- pred get_condition(term::in, term::out, condition::out) is det.
get_condition(Body, Body, cond_true).
% % NU-Prolog supported type declarations of the form
% % :- pred p(T) where p(X) : sorted(X).
% % or
% % :- type sorted_list(T) = list(T) where X : sorted(X).
% % :- pred p(sorted_list(T).
% % There is some code here to support that sort of thing, but
% % probably we would now need to use a different syntax, since
% % Mercury now uses `where' for different purposes (e.g. specifying
% % user-defined equality predicates, and also for type classes ...)
%
% get_condition(B, Body, Condition) :-
% (
% B = term.functor(term.atom("where"), [Body1, Condition1],
% _Context)
% ->
% Body = Body1,
% Condition = where(Condition1)
% ;
% Body = B,
% Condition = true
% ).
%-----------------------------------------------------------------------------%
:- type processed_type_body
---> processed_type_body(
sym_name,
list(type_param),
type_defn
).
%-----------------------------------------------------------------------------%
:- pred process_solver_type(module_name::in, term::in,
maybe(solver_type_details)::in, maybe(unify_compare)::in,
maybe1(processed_type_body)::out) is det.
process_solver_type(ModuleName, Head, MaybeSolverTypeDetails, MaybeUserEqComp,
Result) :-
(
MaybeSolverTypeDetails = yes(SolverTypeDetails),
dummy_term(Body),
parse_type_defn_head(ModuleName, Head, Body, Result0),
(
Result0 = error2(Errors),
Result = error1(Errors)
;
Result0 = ok2(Name, Params),
(
RepnType = SolverTypeDetails ^ representation_type,
type_contains_var(RepnType, Var),
not list.member(Var, Params)
->
Msg = "free type variable in representation type",
Result = error1([Msg - Head])
;
Result = ok1(processed_type_body(Name, Params,
parse_tree_solver_type(SolverTypeDetails,
MaybeUserEqComp)))
)
)
;
MaybeSolverTypeDetails = no,
Result = error1(["solver type with no solver_type_details" - Head])
).
%-----------------------------------------------------------------------------%
% This is for "Head == Body" (equivalence) definitions.
%
:- pred process_eqv_type(module_name::in, term::in, term::in,
maybe1(processed_type_body)::out) is det.
process_eqv_type(ModuleName, Head, Body, Result) :-
parse_type_defn_head(ModuleName, Head, Body, Result0),
process_eqv_type_2(Result0, Body, Result).
:- pred process_eqv_type_2(maybe2(sym_name, list(type_param))::in, term::in,
maybe1(processed_type_body)::out) is det.
process_eqv_type_2(error2(Errors), _, error1(Errors)).
process_eqv_type_2(ok2(Name, Params), Body0, Result) :-
% Check that all the variables in the body occur in the head.
(
term.contains_var(Body0, Var),
term.coerce_var(Var, TVar),
\+ list.member(TVar, Params)
->
Msg = "free type parameter in RHS of type definition",
Result = error1([Msg - Body0])
;
parse_type(Body0, BodyResult),
(
BodyResult = ok1(Body),
Result = ok1(processed_type_body(Name, Params,
parse_tree_eqv_type(Body)))
;
BodyResult = error1(Errors),
Result = error1(Errors)
)
).
%-----------------------------------------------------------------------------%
% process_du_type(ModuleName, TypeHead, TypeBody,
% MaybeUserEqComp, Result):
%
% Checks that its arguments are well formed, and if they are,
% binds Result to a representation of the type information about the
% TypeHead.
% This is for "Head ---> Body [where ...]" (constructor) definitions.
%
:- pred process_du_type(module_name::in, term::in, term::in,
list(constructor)::in, maybe(unify_compare)::in,
maybe1(processed_type_body)::out) is det.
process_du_type(ModuleName, Head, Body, Ctors, MaybeUserEqComp, Result) :-
parse_type_defn_head(ModuleName, Head, Body, Result0),
(
Result0 = error2(Errors),
Result = error1(Errors)
;
Result0 = ok2(Functor, Params),
process_du_type_2(Functor, Params, Body, Ctors, MaybeUserEqComp,
Result)
).
:- pred process_du_type_2(sym_name::in, list(type_param)::in, term::in,
list(constructor)::in, maybe(unify_compare)::in,
maybe1(processed_type_body)::out) is det.
process_du_type_2(Functor, Params, Body, Ctors, MaybeUserEqComp, Result) :-
process_du_ctors(Params, Ctors, CtorsResult),
(
CtorsResult = ok,
TypeDefn = parse_tree_du_type(Ctors, MaybeUserEqComp),
ProcessedTypeBody = processed_type_body(Functor, Params, TypeDefn),
Result = ok1(ProcessedTypeBody)
;
CtorsResult = error(Msg),
Result = error1([Msg - Body])
).
:- pred process_du_ctors(list(type_param)::in, list(constructor)::in,
maybe_error::out) is det.
process_du_ctors(_Params, [], ok).
process_du_ctors(Params, [Ctor | Ctors], Result) :-
Ctor = ctor(ExistQVars, Constraints, _CtorName, CtorArgs, _Conetxt),
(
% Check that all type variables in the ctor are either explicitly
% existentially quantified or occur in the head of the type.
%
CtorArgTypes = list.map(func(C) = C ^ arg_type, CtorArgs),
type_list_contains_var(CtorArgTypes, Var),
\+ list.member(Var, ExistQVars),
\+ list.member(Var, Params)
->
Result = error("free type parameter in RHS of type definition")
;
% Check that all type variables in existential quantifiers do not
% occur in the head (maybe this should just be a warning, not an error?
% If we were to allow it, we would need to rename them apart.)
%
list.member(Var, ExistQVars),
list.member(Var, Params)
->
Result = error("type variable has overlapping scopes " ++
"(explicit type quantifier shadows argument type)")
;
% Check that all type variables in existential quantifiers occur
% somewhere in the constructor argument types or constraints.
%
list.member(Var, ExistQVars),
CtorArgTypes = list.map(func(C) = C ^ arg_type, CtorArgs),
\+ type_list_contains_var(CtorArgTypes, Var),
constraint_list_get_tvars(Constraints, ConstraintTVars),
\+ list.member(Var, ConstraintTVars)
->
Result = error("type variable in existential quantifier " ++
"does not occur in arguments or constraints of constructor")
;
% Check that all type variables in existential constraints occur in
% the existential quantifiers.
%
list.member(Constraint, Constraints),
Constraint = constraint(_Name, ConstraintArgs),
type_list_contains_var(ConstraintArgs, Var),
\+ list.member(Var, ExistQVars)
->
Result = error("type variables in class constraints introduced" ++
" with `=>' must be explicitly existentially quantified" ++
" using `some'")
;
process_du_ctors(Params, Ctors, Result)
).
%-----------------------------------------------------------------------------%
% process_abstract_type(ModuleName, TypeHead, Result):
%
% Checks that its argument is well formed, and if it is, binds Result
% to a representation of the type information about the TypeHead.
%
:- pred process_abstract_type(module_name::in, term::in, decl_attrs::in,
maybe1(processed_type_body)::out) is det.
process_abstract_type(ModuleName, Head, Attributes0, Result) :-
dummy_term(Body),
parse_type_defn_head(ModuleName, Head, Body, Result0),
get_is_solver_type(IsSolverType, Attributes0, Attributes),
process_abstract_type_2(Result0, IsSolverType, Result1),
check_no_attributes(Result1, Attributes, Result).
:- pred process_abstract_type_2(maybe2(sym_name, list(type_param))::in,
is_solver_type::in, maybe1(processed_type_body)::out) is det.
process_abstract_type_2(error2(Errors), _, error1(Errors)).
process_abstract_type_2(ok2(Functor, Params), IsSolverType, Result) :-
Result = ok1(processed_type_body(Functor, Params,
parse_tree_abstract_type(IsSolverType))).
%-----------------------------------------------------------------------------%
parse_type_defn_head(ModuleName, Head, Body, Result) :-
( Head = term.variable(_, _) ->
% `Head' has no term.context, so we need to get the
% context from `Body'.
( Body = term.functor(_, _, Context) ->
dummy_term_with_context(Context, ErrorTerm)
;
dummy_term(ErrorTerm)
),
Result = error2(["variable on LHS of type definition" - ErrorTerm])
;
parse_implicitly_qualified_term(ModuleName, Head, Head,
"type definition", Headresult),
parse_type_defn_head_2(Headresult, Head, Result)
).
:- pred parse_type_defn_head_2(maybe_functor::in, term::in,
maybe2(sym_name, list(tvar))::out) is det.
parse_type_defn_head_2(error2(Errors), _, error2(Errors)).
parse_type_defn_head_2(ok2(Name, Args), Head, Result) :-
parse_type_defn_head_3(Name, Args, Head, Result).
:- pred parse_type_defn_head_3(sym_name::in, list(term)::in, term::in,
maybe2(sym_name, list(tvar))::out) is det.
parse_type_defn_head_3(Name, Args, Head, Result) :-
% Check that all the head args are variables.
( term_list_to_var_list(Args, Params0) ->
% Check that all the head arg variables are distinct.
(
list.member(_, Params0, [Param | OtherParams]),
list.member(Param, OtherParams)
->
Msg = "repeated type parameters in LHS of type defn",
Result = error2([Msg - Head])
;
list.map(term.coerce_var, Params0, Params),
Result = ok2(Name, Params)
)
;
Result = error2(["type parameters must be variables" - Head])
).
%-----------------------------------------------------------------------------%
% Convert a list of terms separated by semi-colons (known as a
% "disjunction", even thought the terms aren't goals in this case)
% into a list of constructors.
%
:- func convert_constructors(module_name, term) = maybe1(list(constructor)).
convert_constructors(ModuleName, Body) = Result :-
disjunction_to_list(Body, List),
Result = convert_constructors_2(ModuleName, List).
% True if input argument is a valid list of constructors.
%
:- func convert_constructors_2(module_name, list(term)) =
maybe1(list(constructor)).
convert_constructors_2(_ModuleName, []) = ok1([]).
convert_constructors_2( ModuleName, [Term | Terms]) = Result :-
Result0 = convert_constructor(ModuleName, Term),
(
Result0 = error1(Errors),
Result = error1(Errors)
;
Result0 = ok1(Constructor),
Result1 = convert_constructors_2(ModuleName, Terms),
(
Result1 = error1(Errors),
Result = error1(Errors)
;
Result1 = ok1(Constructors),
Result = ok1([Constructor | Constructors])
)
).
:- func convert_constructor(module_name, term) = maybe1(constructor).
convert_constructor(ModuleName, Term0) = Result :-
( Term0 = term.functor(term.atom("some"), [Vars, Term1], _Context) ->
( parse_list_of_vars(Vars, ExistQVars0) ->
list.map(term.coerce_var, ExistQVars0, ExistQVars),
Result = convert_constructor_2(ModuleName, ExistQVars,
Term0, Term1)
;
Result = error1(["syntax error in variable list" - Term0])
)
;
ExistQVars = [],
Result = convert_constructor_2(ModuleName, ExistQVars, Term0, Term0)
).
:- func convert_constructor_2(module_name, list(tvar), term, term) =
maybe1(constructor).
convert_constructor_2(ModuleName, ExistQVars, Term0, Term1) = Result :-
get_existential_constraints_from_term(ModuleName, Term1, Term2, Result0),
(
Result0 = error1(Errors),
Result = error1(Errors)
;
Result0 = ok1(Constraints),
(
% Note that as a special case, one level of curly braces around
% the constructor are ignored. This is to allow you to define
% ';'/2 and 'some'/2 constructors.
Term2 = term.functor(term.atom("{}"), [Term3], _Context)
->
Term4 = Term3
;
Term4 = Term2
),
Result = convert_constructor_3(ModuleName, ExistQVars, Constraints,
Term0, Term4)
).
:- func convert_constructor_3(module_name, list(tvar), list(prog_constraint),
term, term) = maybe1(constructor).
convert_constructor_3(ModuleName, ExistQVars, Constraints, Term0, Term1) =
Result :-
parse_implicitly_qualified_term(ModuleName, Term1, Term0,
"constructor definition", Result0),
(
Result0 = error2(Errors),
Result = error1(Errors)
;
Result0 = ok2(F, As),
Result1 = convert_constructor_arg_list(ModuleName, As),
(
Result1 = error1(Errors),
Result = error1(Errors)
;
Result1 = ok1(Args),
Ctxt = term_context(Term1),
Result = ok1(ctor(ExistQVars, Constraints, F, Args, Ctxt))
)
).
:- func term_context(term(T)) = prog_context.
term_context(functor(_, _, C)) = C.
term_context(variable(_, C)) = C.
%-----------------------------------------------------------------------------%
% parse a `:- pred p(...)' declaration or a
% `:- func f(...) `with_type` t' declaration
%
:- pred process_pred_or_func(pred_or_func::in, module_name::in, varset::in,
term::in, condition::in, maybe(mer_type)::in, maybe(mer_inst)::in,
maybe(determinism)::in, decl_attrs::in, maybe1(item)::out) is det.
process_pred_or_func(PredOrFunc, ModuleName, VarSet, PredType, Cond, WithType,
WithInst, MaybeDet, Attributes0, Result) :-
get_class_context_and_inst_constraints(ModuleName, Attributes0,
Attributes, MaybeContext),
(
MaybeContext = ok3(ExistQVars, Constraints, InstConstraints),
parse_implicitly_qualified_term(ModuleName, PredType, PredType,
pred_or_func_decl_string(PredOrFunc), R),
process_pred_or_func_2(PredOrFunc, R, PredType, VarSet,
WithType, WithInst, MaybeDet, Cond, ExistQVars,
Constraints, InstConstraints, Attributes, Result)
;
MaybeContext = error3(Errors),
Result = error1(Errors)
).
:- pred process_pred_or_func_2(pred_or_func::in, maybe_functor::in, term::in,
varset::in, maybe(mer_type)::in, maybe(mer_inst)::in,
maybe(determinism)::in, condition::in, existq_tvars::in,
prog_constraints::in, inst_var_sub::in, decl_attrs::in, maybe1(item)::out)
is det.
process_pred_or_func_2(_, error2(Errors), _, _, _, _, _, _, _, _, _, _,
error1(Errors)).
process_pred_or_func_2(PredOrFunc, ok2(F, As0), PredType, VarSet0,
WithType, WithInst, MaybeDet, Cond, ExistQVars,
ClassContext, InstConstraints, Attributes0, Result) :-
( convert_type_and_mode_list(InstConstraints, As0, As) ->
( verify_type_and_mode_list(As) ->
(
WithInst = yes(_),
As = [type_only(_) | _]
->
Msg = "`with_inst` specified without argument modes",
Result = error1([Msg - PredType])
;
WithInst = no,
WithType = yes(_),
As = [type_and_mode(_, _) | _]
->
Msg = "arguments have modes but `with_inst` not specified",
Result = error1([Msg - PredType])
;
\+ inst_var_constraints_are_consistent_in_type_and_modes(As)
->
Msg = "inconsistent constraints on inst variables in " ++
pred_or_func_decl_string(PredOrFunc),
Result = error1([Msg - PredType])
;
get_purity(Purity, Attributes0, Attributes),
varset.coerce(VarSet0, TVarSet),
varset.coerce(VarSet0, IVarSet),
Origin = user,
Result0 = ok1(item_pred_or_func(Origin, TVarSet, IVarSet,
ExistQVars, PredOrFunc, F, As, WithType, WithInst,
MaybeDet, Cond, Purity, ClassContext)),
check_no_attributes(Result0, Attributes, Result)
)
;
Msg = "some but not all arguments have modes",
Result = error1([Msg - PredType])
)
;
Msg = "syntax error in " ++ pred_or_func_decl_string(PredOrFunc),
Result = error1([Msg - PredType])
).
:- pred get_purity(purity::out, decl_attrs::in, decl_attrs::out) is det.
get_purity(Purity, !Attributes) :-
( !.Attributes = [decl_attr_purity(Purity0) - _ | !:Attributes] ->
Purity = Purity0
;
Purity = purity_pure
).
:- func pred_or_func_decl_string(pred_or_func) = string.
pred_or_func_decl_string(pf_function) = "`:- func' declaration".
pred_or_func_decl_string(pf_predicate) = "`:- pred' declaration".
%-----------------------------------------------------------------------------%
% We could perhaps get rid of some code duplication between here and
% prog_io_typeclass.m?
% get_class_context_and_inst_constraints(ModuleName, Attributes0,
% Attributes, MaybeContext, MaybeInstConstraints):
%
% Parse type quantifiers, type class constraints and inst constraints
% from the declaration attributes in Attributes0.
% MaybeContext is either bound to the correctly parsed context, or
% an appropriate error message (if there was a syntax error).
% MaybeInstConstraints is either bound to a map containing the inst
% constraints or an appropriate error message (if there was a syntax
% error).
% Attributes is bound to the remaining attributes.
%
:- pred get_class_context_and_inst_constraints(module_name::in,
decl_attrs::in, decl_attrs::out,
maybe3(existq_tvars, prog_constraints, inst_var_sub)::out) is det.
get_class_context_and_inst_constraints(ModuleName, RevAttributes0,
RevAttributes, MaybeContext) :-
% Constraints and quantifiers should occur in the following order
% (outermost to innermost):
%
% operator precedence
% -------- ----------
% 1. universal quantifiers all 950
% 2. existential quantifiers some 950
% 3. universal constraints <= 920
% 4. existential constraints => 920 [*]
% 5. the decl itself pred or func 800
%
% When we reach here, Attributes0 contains declaration attributes
% in the opposite order -- innermost to outermost -- so we reverse
% them before we start.
%
% [*] Note that the semantic meaning of `=>' is not quite the same
% as implication; logically speaking it's more like conjunction.
% Oh well, at least it has the right precedence.
%
% In theory it could make sense to allow the order of 2 & 3 to be
% swapped, or (in the case of multiple constraints & multiple
% quantifiers) to allow arbitrary interleaving of 2 & 3, but in
% practice it seems there would be little benefit in allowing that
% flexibility, so we don't.
%
% Universal quantification is the default, so we just ignore
% universal quantifiers. (XXX It might be a good idea to check
% that any universally quantified type variables do actually
% occur somewhere in the type declaration, and are not also
% existentially quantified, and if not, issue a warning or
% error message.)
list.reverse(RevAttributes0, Attributes0),
get_quant_vars(quant_type_univ, ModuleName, Attributes0, Attributes1,
[], _UnivQVars),
get_quant_vars(quant_type_exist, ModuleName, Attributes1, Attributes2,
[], ExistQVars0),
list.map(term.coerce_var, ExistQVars0, ExistQVars),
get_constraints(quant_type_univ, ModuleName, Attributes2,
Attributes3, MaybeUnivConstraints),
get_constraints(quant_type_exist, ModuleName, Attributes3,
Attributes, MaybeExistConstraints),
list.reverse(Attributes, RevAttributes),
combine_quantifier_results(MaybeUnivConstraints, MaybeExistConstraints,
ExistQVars, MaybeContext).
:- pred combine_quantifier_results(maybe_class_and_inst_constraints::in,
maybe_class_and_inst_constraints::in, existq_tvars::in,
maybe3(existq_tvars, prog_constraints, inst_var_sub)::out) is det.
combine_quantifier_results(error2(Errors1), error2(Errors2), _,
error3(Errors1 ++ Errors2)).
combine_quantifier_results(error2(Errors), ok2(_, _), _, error3(Errors)).
combine_quantifier_results(ok2(_, _), error2(Errors), _, error3(Errors)).
combine_quantifier_results(ok2(UnivConstraints, InstConstraints0),
ok2(ExistConstraints, InstConstraints1), ExistQVars,
ok3(ExistQVars, constraints(UnivConstraints, ExistConstraints),
InstConstraints0 `map.old_merge` InstConstraints1)).
:- pred get_quant_vars(quantifier_type::in, module_name::in,
decl_attrs::in, decl_attrs::out, list(var)::in, list(var)::out) is det.
get_quant_vars(QuantType, ModuleName, !Attributes, !Vars) :-
(
!.Attributes = [decl_attr_quantifier(QuantType, QuantVars) - _
| !:Attributes]
->
list.append(!.Vars, QuantVars, !:Vars),
get_quant_vars(QuantType, ModuleName, !Attributes, !Vars)
;
true
).
:- pred get_constraints(quantifier_type::in, module_name::in, decl_attrs::in,
decl_attrs::out, maybe_class_and_inst_constraints::out) is det.
get_constraints(QuantType, ModuleName, !Attributes, MaybeConstraints) :-
(
!.Attributes = [
decl_attr_constraints(QuantType, ConstraintsTerm) - _Term
| !:Attributes]
->
parse_class_and_inst_constraints(ModuleName, ConstraintsTerm,
MaybeConstraints0),
% there may be more constraints of the same type --
% collect them all and combine them
get_constraints(QuantType, ModuleName, !Attributes, MaybeConstraints1),
combine_constraint_list_results(MaybeConstraints1,
MaybeConstraints0, MaybeConstraints)
;
MaybeConstraints = ok2([], map.init)
).
:- pred combine_constraint_list_results(maybe_class_and_inst_constraints::in,
maybe_class_and_inst_constraints::in,
maybe_class_and_inst_constraints::out) is det.
combine_constraint_list_results(error2(Errors1), error2(Errors2),
error2(Errors1 ++ Errors2)).
combine_constraint_list_results(error2(Errors), ok2(_, _), error2(Errors)).
combine_constraint_list_results(ok2(_, _), error2(Errors), error2(Errors)).
combine_constraint_list_results(ok2(CC0, IC0), ok2(CC1, IC1),
ok2(CC0 ++ CC1, IC0 `map.old_merge` IC1)).
:- pred get_existential_constraints_from_term(module_name::in,
term::in, term::out, maybe1(list(prog_constraint))::out) is det.
get_existential_constraints_from_term(ModuleName, !PredType,
MaybeExistentialConstraints) :-
(
!.PredType = term.functor(term.atom("=>"),
[!:PredType, ExistentialConstraints], _)
->
parse_class_constraints(ModuleName, ExistentialConstraints,
MaybeExistentialConstraints)
;
MaybeExistentialConstraints = ok1([])
).
%-----------------------------------------------------------------------------%
% Verify that among the arguments of a :- pred declaration,
% either all arguments specify a mode or none of them do.
%
:- pred verify_type_and_mode_list(list(type_and_mode)::in) is semidet.
verify_type_and_mode_list([]).
verify_type_and_mode_list([First | Rest]) :-
verify_type_and_mode_list_2(Rest, First).
:- pred verify_type_and_mode_list_2(list(type_and_mode)::in, type_and_mode::in)
is semidet.
verify_type_and_mode_list_2([], _).
verify_type_and_mode_list_2([Head | Tail], First) :-
(
Head = type_only(_),
First = type_only(_)
;
Head = type_and_mode(_, _),
First = type_and_mode(_, _)
),
verify_type_and_mode_list_2(Tail, First).
%-----------------------------------------------------------------------------%
% Parse a `:- func p(...)' declaration.
%
:- pred process_func(module_name::in, varset::in, term::in, condition::in,
maybe(determinism)::in, decl_attrs::in, maybe1(item)::out) is det.
process_func(ModuleName, VarSet, Term, Cond, MaybeDet, Attributes0, Result) :-
get_class_context_and_inst_constraints(ModuleName, Attributes0,
Attributes, MaybeContext),
(
MaybeContext = ok3(ExistQVars, Constraints, InstConstraints),
process_func_2(ModuleName, VarSet, Term, Cond, MaybeDet, ExistQVars,
Constraints, InstConstraints, Attributes, Result)
;
MaybeContext = error3(Errors),
Result = error1(Errors)
).
:- pred process_func_2(module_name::in, varset::in, term::in, condition::in,
maybe(determinism)::in, existq_tvars::in, prog_constraints::in,
inst_var_sub::in, decl_attrs::in, maybe1(item)::out) is det.
process_func_2(ModuleName, VarSet, Term, Cond, MaybeDet, ExistQVars,
Constraints, InstConstraints, Attributes, Result) :-
(
Term = term.functor(term.atom("="),
[FuncTerm0, ReturnTypeTerm], _Context),
FuncTerm = desugar_field_access(FuncTerm0)
->
parse_implicitly_qualified_term(ModuleName, FuncTerm, Term,
"`:- func' declaration", R),
process_func_3(R, FuncTerm, ReturnTypeTerm, Term, VarSet, MaybeDet,
Cond, ExistQVars, Constraints, InstConstraints, Attributes, Result)
;
Result = error1(["`=' expected in `:- func' declaration" - Term])
).
:- pred process_func_3(maybe_functor::in, term::in, term::in, term::in,
varset::in, maybe(determinism)::in, condition::in, existq_tvars::in,
prog_constraints::in, inst_var_sub::in, decl_attrs::in,
maybe1(item)::out) is det.
process_func_3(error2(Errors), _, _, _, _, _, _, _, _, _, _, error1(Errors)).
process_func_3(ok2(F, As0), FuncTerm, ReturnTypeTerm, FullTerm, VarSet0,
MaybeDet, Cond, ExistQVars, ClassContext, InstConstraints,
Attributes0, Result) :-
( convert_type_and_mode_list(InstConstraints, As0, As) ->
(
\+ verify_type_and_mode_list(As)
->
Msg = "some but not all arguments have modes",
Result = error1([Msg - FuncTerm])
;
convert_type_and_mode(InstConstraints, ReturnTypeTerm, ReturnType)
->
(
As = [type_and_mode(_, _) | _],
ReturnType = type_only(_)
->
Msg = "function arguments have modes, " ++
"but function result doesn't",
Result = error1([Msg - FuncTerm])
;
As = [type_only(_) | _],
ReturnType = type_and_mode(_, _)
->
Msg = "function result has mode, but function arguments don't",
Result = error1([Msg - FuncTerm])
;
get_purity(Purity, Attributes0, Attributes),
varset.coerce(VarSet0, TVarSet),
varset.coerce(VarSet0, IVarSet),
list.append(As, [ReturnType], Args),
(
inst_var_constraints_are_consistent_in_type_and_modes(Args)
->
Origin = user,
Result0 = ok1(item_pred_or_func(Origin, TVarSet, IVarSet,
ExistQVars, pf_function, F, Args, no, no, MaybeDet,
Cond, Purity, ClassContext)),
check_no_attributes(Result0, Attributes, Result)
;
Msg = "inconsistent constraints on inst variables " ++
"in function declaration",
Result = error1([Msg - FullTerm])
)
)
;
Msg = "syntax error in return type of `:- func' declaration",
Result = error1([Msg - ReturnTypeTerm])
)
;
Msg = "syntax error in arguments of `:- func' declaration",
Result = error1([Msg - FuncTerm])
).
%-----------------------------------------------------------------------------%
% Perform one of the following field-access syntax rewrites if possible:
%
% A ^ f(B, ...) ---> f(B, ..., A)
% (A ^ f(B, ...) := X) ---> 'f :='(B, ..., A, X)
%
:- func desugar_field_access(term) = term.
desugar_field_access(Term) =
(
Term = functor(atom("^"), [A, RHS], _),
RHS = functor(atom(FieldName), Bs, Context)
->
functor(atom(FieldName), Bs ++ [A], Context)
;
Term = functor(atom(":="), [LHS, X], _),
LHS = functor(atom("^"), [A, RHS], Context),
RHS = functor(atom(FieldName), Bs, Context)
->
functor(atom(FieldName ++ " :="), Bs ++ [A, X], Context)
;
Term
).
%-----------------------------------------------------------------------------%
% Parse a `:- mode p(...)' declaration.
%
:- pred process_mode(module_name::in, varset::in, term::in, condition::in,
decl_attrs::in, maybe(mer_inst)::in, maybe(determinism)::in,
maybe1(item)::out) is det.
process_mode(ModuleName, VarSet, Term, Cond, Attributes, WithInst, MaybeDet,
Result) :-
(
WithInst = no,
Term = term.functor(term.atom("="), [FuncTerm0, ReturnTypeTerm],
_Context),
FuncTerm = desugar_field_access(FuncTerm0)
->
parse_implicitly_qualified_term(ModuleName, FuncTerm, Term,
"function `:- mode' declaration", R),
process_func_mode(R, ModuleName, FuncTerm, ReturnTypeTerm,
Term, VarSet, MaybeDet, Cond, Attributes, Result)
;
parse_implicitly_qualified_term(ModuleName, Term, Term,
"`:- mode' declaration", R),
process_pred_or_func_mode(R, ModuleName, Term, VarSet,
WithInst, MaybeDet, Cond, Attributes, Result)
).
:- pred process_pred_or_func_mode(maybe_functor::in, module_name::in, term::in,
varset::in, maybe(mer_inst)::in, maybe(determinism)::in, condition::in,
decl_attrs::in, maybe1(item)::out) is det.
process_pred_or_func_mode(error2(Errors), _, _, _, _, _, _, _, error1(Errors)).
process_pred_or_func_mode(ok2(F, As0), ModuleName, PredMode, VarSet0, WithInst,
MaybeDet, Cond, Attributes0, Result) :-
( convert_mode_list(allow_constrained_inst_var, As0, As1) ->
get_class_context_and_inst_constraints(ModuleName, Attributes0,
Attributes, MaybeConstraints),
(
MaybeConstraints = ok3(_, _, InstConstraints),
list.map(constrain_inst_vars_in_mode(InstConstraints), As1, As),
varset.coerce(VarSet0, VarSet),
( inst_var_constraints_are_consistent_in_modes(As) ->
(
WithInst = no,
PredOrFunc = yes(pf_predicate)
;
WithInst = yes(_),
% We don't know whether it's a predicate or a function
% until we expand out the inst.
PredOrFunc = no
),
Result0 = ok1(item_pred_or_func_mode(VarSet, PredOrFunc, F, As,
WithInst, MaybeDet, Cond))
;
Msg = "inconsistent constraints on inst variables " ++
"in predicate mode declaration",
Result0 = error1([Msg - PredMode])
)
;
MaybeConstraints = error3(Errors),
Result0 = error1(Errors)
),
check_no_attributes(Result0, Attributes, Result)
;
Result = error1(["syntax error in mode declaration" - PredMode])
).
:- pred process_func_mode(maybe_functor::in, module_name::in, term::in,
term::in, term::in, varset::in, maybe(determinism)::in, condition::in,
decl_attrs::in, maybe1(item)::out) is det.
process_func_mode(error2(Errors), _, _, _, _, _, _, _, _, error1(Errors)).
process_func_mode(ok2(F, As0), ModuleName, FuncMode, RetMode0, FullTerm,
VarSet0, MaybeDet, Cond, Attributes0, Result) :-
(
convert_mode_list(allow_constrained_inst_var, As0, As1)
->
get_class_context_and_inst_constraints(ModuleName, Attributes0,
Attributes, MaybeConstraints),
(
MaybeConstraints = ok3(_, _, InstConstraints),
list.map(constrain_inst_vars_in_mode(InstConstraints), As1, As),
(
convert_mode(allow_constrained_inst_var, RetMode0, RetMode1)
->
constrain_inst_vars_in_mode(InstConstraints,
RetMode1, RetMode),
varset.coerce(VarSet0, VarSet),
list.append(As, [RetMode], ArgModes),
( inst_var_constraints_are_consistent_in_modes(ArgModes) ->
Result0 = ok1(item_pred_or_func_mode(VarSet,
yes(pf_function), F, ArgModes, no, MaybeDet, Cond))
;
Msg = "inconsistent constraints on inst variables " ++
"in function mode declaration",
Result0 = error1([Msg - FullTerm])
)
;
Msg = "syntax error in return mode " ++
"of function mode declaration",
Result0 = error1([Msg - RetMode0])
)
;
MaybeConstraints = error3(Errors),
Result0 = error1(Errors)
),
check_no_attributes(Result0, Attributes, Result)
;
Msg = "syntax error in arguments of function mode declaration",
Result = error1([Msg - FuncMode])
).
%-----------------------------------------------------------------------------%
constrain_inst_vars_in_mode(Mode0, Mode) :-
constrain_inst_vars_in_mode(map.init, Mode0, Mode).
constrain_inst_vars_in_mode(InstConstraints, I0 -> F0, I -> F) :-
constrain_inst_vars_in_inst(InstConstraints, I0, I),
constrain_inst_vars_in_inst(InstConstraints, F0, F).
constrain_inst_vars_in_mode(InstConstraints, user_defined_mode(Name, Args0),
user_defined_mode(Name, Args)) :-
list.map(constrain_inst_vars_in_inst(InstConstraints), Args0, Args).
:- pred constrain_inst_vars_in_inst(inst_var_sub::in,
mer_inst::in, mer_inst::out) is det.
constrain_inst_vars_in_inst(_, any(U), any(U)).
constrain_inst_vars_in_inst(_, free, free).
constrain_inst_vars_in_inst(_, free(T), free(T)).
constrain_inst_vars_in_inst(InstConstraints, bound(U, BIs0), bound(U, BIs)) :-
list.map(
(pred(bound_functor(C, Is0)::in, bound_functor(C, Is)::out) is det :-
list.map(constrain_inst_vars_in_inst(InstConstraints), Is0, Is)),
BIs0, BIs).
constrain_inst_vars_in_inst(_, ground(U, none), ground(U, none)).
constrain_inst_vars_in_inst(InstConstraints,
ground(U, higher_order(PredInstInfo0)),
ground(U, higher_order(PredInstInfo))) :-
constrain_inst_vars_in_pred_inst_info(InstConstraints, PredInstInfo0,
PredInstInfo).
constrain_inst_vars_in_inst(InstConstraints,
constrained_inst_vars(Vars0, Inst0),
constrained_inst_vars(Vars, Inst)) :-
constrain_inst_vars_in_inst(InstConstraints, Inst0, Inst1),
( Inst1 = constrained_inst_vars(Vars2, Inst2) ->
Vars = Vars0 `set.union` Vars2,
Inst = Inst2
;
Vars = Vars0,
Inst = Inst1
).
constrain_inst_vars_in_inst(_, not_reached, not_reached).
constrain_inst_vars_in_inst(InstConstraints, inst_var(Var),
constrained_inst_vars(set.make_singleton_set(Var), Inst)) :-
( map.search(InstConstraints, Var, Inst0) ->
Inst = Inst0
;
Inst = ground(shared, none)
).
constrain_inst_vars_in_inst(InstConstraints, defined_inst(Name0),
defined_inst(Name)) :-
constrain_inst_vars_in_inst_name(InstConstraints, Name0, Name).
constrain_inst_vars_in_inst(InstConstraints, abstract_inst(N, Is0),
abstract_inst(N, Is)) :-
list.map(constrain_inst_vars_in_inst(InstConstraints), Is0, Is).
:- pred constrain_inst_vars_in_pred_inst_info(inst_var_sub::in,
pred_inst_info::in, pred_inst_info::out) is det.
constrain_inst_vars_in_pred_inst_info(InstConstraints, PII0, PII) :-
PII0 = pred_inst_info(PredOrFunc, Modes0, Det),
list.map(constrain_inst_vars_in_mode(InstConstraints), Modes0, Modes),
PII = pred_inst_info(PredOrFunc, Modes, Det).
:- pred constrain_inst_vars_in_inst_name(inst_var_sub::in,
inst_name::in, inst_name::out) is det.
constrain_inst_vars_in_inst_name(InstConstraints, Name0, Name) :-
( Name0 = user_inst(SymName, Args0) ->
list.map(constrain_inst_vars_in_inst(InstConstraints), Args0, Args),
Name = user_inst(SymName, Args)
;
Name = Name0
).
%-----------------------------------------------------------------------------%
inst_var_constraints_are_consistent_in_modes(Modes) :-
inst_var_constraints_are_consistent_in_modes(Modes, map.init, _).
:- pred inst_var_constraints_are_consistent_in_modes(list(mer_mode)::in,
inst_var_sub::in, inst_var_sub::out) is semidet.
inst_var_constraints_are_consistent_in_modes(Modes, !Sub) :-
list.foldl(inst_var_constraints_are_consistent_in_mode, Modes, !Sub).
:- pred inst_var_constraints_are_consistent_in_type_and_modes(
list(type_and_mode)::in) is semidet.
inst_var_constraints_are_consistent_in_type_and_modes(TypeAndModes) :-
list.foldl((pred(TypeAndMode::in, in, out) is semidet -->
( { TypeAndMode = type_only(_) }
; { TypeAndMode = type_and_mode(_, Mode) },
inst_var_constraints_are_consistent_in_mode(Mode)
)), TypeAndModes, map.init, _).
:- pred inst_var_constraints_are_consistent_in_mode(mer_mode::in,
inst_var_sub::in, inst_var_sub::out) is semidet.
inst_var_constraints_are_consistent_in_mode(InitialInst -> FinalInst, !Sub) :-
inst_var_constraints_are_consistent_in_inst(InitialInst, !Sub),
inst_var_constraints_are_consistent_in_inst(FinalInst, !Sub).
inst_var_constraints_are_consistent_in_mode(user_defined_mode(_, ArgInsts),
!Sub) :-
inst_var_constraints_are_consistent_in_insts(ArgInsts, !Sub).
:- pred inst_var_constraints_are_consistent_in_insts(list(mer_inst)::in,
inst_var_sub::in, inst_var_sub::out) is semidet.
inst_var_constraints_are_consistent_in_insts(Insts, !Sub) :-
list.foldl(inst_var_constraints_are_consistent_in_inst, Insts, !Sub).
:- pred inst_var_constraints_are_consistent_in_inst(mer_inst::in,
inst_var_sub::in, inst_var_sub::out) is semidet.
inst_var_constraints_are_consistent_in_inst(any(_), !Sub).
inst_var_constraints_are_consistent_in_inst(free, !Sub).
inst_var_constraints_are_consistent_in_inst(free(_), !Sub).
inst_var_constraints_are_consistent_in_inst(bound(_, BoundInsts), !Sub) :-
list.foldl(
(pred(bound_functor(_, Insts)::in, in, out) is semidet -->
inst_var_constraints_are_consistent_in_insts(Insts)),
BoundInsts, !Sub).
inst_var_constraints_are_consistent_in_inst(ground(_, GroundInstInfo), !Sub) :-
(
GroundInstInfo = none
;
GroundInstInfo = higher_order(pred_inst_info(_, Modes, _)),
inst_var_constraints_are_consistent_in_modes(Modes, !Sub)
).
inst_var_constraints_are_consistent_in_inst(not_reached, !Sub).
inst_var_constraints_are_consistent_in_inst(inst_var(_), !Sub) :-
unexpected(this_file, "inst_var_constraints_are_consistent_in_inst: " ++
"unconstrained inst_var").
inst_var_constraints_are_consistent_in_inst(defined_inst(InstName), !Sub) :-
( InstName = user_inst(_, Insts) ->
inst_var_constraints_are_consistent_in_insts(Insts, !Sub)
;
true
).
inst_var_constraints_are_consistent_in_inst(abstract_inst(_, Insts), !Sub) :-
inst_var_constraints_are_consistent_in_insts(Insts, !Sub).
inst_var_constraints_are_consistent_in_inst(
constrained_inst_vars(InstVars, Inst), !Sub) :-
set.fold((pred(InstVar::in, in, out) is semidet -->
( Inst0 =^ map.elem(InstVar) ->
% Check that the inst_var constraint is consistent with
% the previous constraint on this inst_var.
{ Inst = Inst0 }
;
^ map.elem(InstVar) := Inst
)), InstVars, !Sub),
inst_var_constraints_are_consistent_in_inst(Inst, !Sub).
%-----------------------------------------------------------------------------%
% Parse a `:- inst <InstDefn>.' declaration.
%
:- pred parse_inst_decl(module_name::in, varset::in, term::in,
maybe1(item)::out) is det.
parse_inst_decl(ModuleName, VarSet, InstDefn, Result) :-
(
InstDefn = term.functor(term.atom(Op), [H, B], _Context),
Op = "=="
->
get_condition(B, Body, Condition),
convert_inst_defn(ModuleName, H, Body, R),
process_maybe1(make_inst_defn(VarSet, Condition), R, Result)
;
% XXX This is for `abstract inst' declarations,
% which are not really supported.
InstDefn = term.functor(term.atom("is"),
[Head, term.functor(term.atom("private"), [], _)], _)
->
Condition = cond_true,
convert_abstract_inst_defn(ModuleName, Head, R),
process_maybe1(make_inst_defn(VarSet, Condition), R, Result)
;
InstDefn = term.functor(term.atom("--->"), [H, B], Context)
->
get_condition(B, Body, Condition),
Body1 = term.functor(term.atom("bound"), [Body], Context),
convert_inst_defn(ModuleName, H, Body1, R),
% We should check the condition for errs (don't bother at the moment,
% since we ignore conditions anyhow :-)
process_maybe1(make_inst_defn(VarSet, Condition), R, Result)
;
Result = error1(["`==' expected in `:- inst' definition" - InstDefn])
).
% Parse a `:- inst <Head> ---> <Body>.' definition.
%
:- pred convert_inst_defn(module_name::in, term::in, term::in,
maybe1(processed_inst_body)::out) is det.
convert_inst_defn(ModuleName, Head, Body, Result) :-
parse_implicitly_qualified_term(ModuleName, Head, Body,
"inst definition", R),
convert_inst_defn_2(R, Head, Body, Result).
:- pred convert_inst_defn_2(maybe_functor::in, term::in, term::in,
maybe1(processed_inst_body)::out) is det.
convert_inst_defn_2(error2(Errors), _, _, error1(Errors)).
convert_inst_defn_2(ok2(Name, ArgTerms), Head, Body, Result) :-
(
% Check that all the head args are variables.
term.term_list_to_var_list(ArgTerms, Args)
->
(
% Check that all the head arg variables are distinct.
list.member(Arg2, Args, [Arg2 | OtherArgs]),
list.member(Arg2, OtherArgs)
->
Msg = "repeated inst parameters in LHS of inst defn",
Result = error1([Msg - Head])
;
% Check that all the variables in the body occur in the head.
term.contains_var(Body, Var2),
\+ list.member(Var2, Args)
->
Msg = "free inst parameter in RHS of inst definition",
Result = error1([Msg - Body])
;
% Check that the inst is a valid user-defined inst, i.e. that it
% does not have the form of one of the builtin insts.
\+ (
convert_inst(no_allow_constrained_inst_var, Head, UserInst),
UserInst = defined_inst(user_inst(_, _))
)
->
Result = error1(["attempt to redefine builtin inst" - Head])
;
% Should improve the error message here.
(
convert_inst(no_allow_constrained_inst_var, Body,
ConvertedBody)
->
list.map(term.coerce_var, Args, InstArgs),
Result = ok1(processed_inst_body(Name, InstArgs,
eqv_inst(ConvertedBody)))
;
Result = error1(["syntax error in inst body" - Body])
)
)
;
Result = error1(["inst parameters must be variables" - Head])
).
:- type processed_inst_body
---> processed_inst_body(
sym_name,
list(inst_var),
inst_defn
).
:- pred convert_abstract_inst_defn(module_name::in, term::in,
maybe1(processed_inst_body)::out) is det.
convert_abstract_inst_defn(ModuleName, Head, Result) :-
parse_implicitly_qualified_term(ModuleName, Head, Head,
"inst definition", R),
convert_abstract_inst_defn_2(R, Head, Result).
:- pred convert_abstract_inst_defn_2(maybe_functor::in, term::in,
maybe1(processed_inst_body)::out) is det.
convert_abstract_inst_defn_2(error2(Errors), _, error1(Errors)).
convert_abstract_inst_defn_2(ok2(Name, ArgTerms), Head, Result) :-
(
% Check that all the head args are variables.
term.term_list_to_var_list(ArgTerms, Args)
->
(
% Check that all the head arg variables are distinct.
list.member(Arg2, Args, [Arg2 | OtherArgs]),
list.member(Arg2, OtherArgs)
->
Msg = "repeated inst parameters in abstract inst definition",
Result = error1([Msg - Head])
;
list.map(term.coerce_var, Args, InstArgs),
Result = ok1(processed_inst_body(Name, InstArgs, abstract_inst))
)
;
Result = error1(["inst parameters must be variables" - Head])
).
:- pred make_inst_defn(varset::in, condition::in, processed_inst_body::in,
item::out) is det.
make_inst_defn(VarSet0, Cond, processed_inst_body(Name, Params, InstDefn),
item_inst_defn(VarSet, Name, Params, InstDefn, Cond)) :-
varset.coerce(VarSet0, VarSet).
%-----------------------------------------------------------------------------%
% Parse a `:- mode foo == ...' definition.
%
:- pred parse_mode_decl(module_name::in, varset::in, term::in, decl_attrs::in,
maybe1(item)::out) is det.
parse_mode_decl(ModuleName, VarSet, ModeDefn, Attributes, Result) :-
( mode_op(ModeDefn, H, B) ->
get_condition(B, Body, Condition),
convert_mode_defn(ModuleName, H, Body, R),
process_maybe1(make_mode_defn(VarSet, Condition), R, Result)
;
parse_mode_decl_pred(ModuleName, VarSet, ModeDefn, Attributes, Result)
).
:- pred mode_op(term::in, term::out, term::out) is semidet.
mode_op(term.functor(term.atom(Op), [H, B], _), H, B) :-
Op = "==".
:- type processed_mode_body
---> processed_mode_body(
sym_name,
list(inst_var),
mode_defn
).
:- pred convert_mode_defn(module_name::in, term::in, term::in,
maybe1(processed_mode_body)::out) is det.
convert_mode_defn(ModuleName, Head, Body, Result) :-
parse_implicitly_qualified_term(ModuleName, Head, Head,
"mode definition", R),
convert_mode_defn_2(R, Head, Body, Result).
:- pred convert_mode_defn_2(maybe_functor::in, term::in, term::in,
maybe1(processed_mode_body)::out) is det.
convert_mode_defn_2(error2(Errors), _, _, error1(Errors)).
convert_mode_defn_2(ok2(Name, ArgTerms), Head, Body, Result) :-
(
% Check that all the head args are variables.
term.term_list_to_var_list(ArgTerms, Args)
->
(
% Check that all the head arg variables are distinct.
list.member(Arg2, Args, [Arg2 | OtherArgs]),
list.member(Arg2, OtherArgs)
->
Msg = "repeated parameters in LHS of mode defn",
Result = error1([Msg - Head])
;
% Check that all the variables in the body occur in the head.
term.contains_var(Body, Var2),
\+ list.member(Var2, Args)
->
Msg = "free inst parameter in RHS of mode definition",
Result = error1([Msg - Head])
;
% Should improve the error message here.
(
convert_mode(no_allow_constrained_inst_var, Body,
ConvertedBody)
->
list.map(term.coerce_var, Args, InstArgs),
Result = ok1(processed_mode_body(Name, InstArgs,
eqv_mode(ConvertedBody)))
;
% Catch-all error message - we should do better than this.
Msg = "syntax error in mode definition body",
Result = error1([Msg - Body])
)
)
;
Result = error1(["mode parameters must be variables" - Head])
).
:- pred convert_type_and_mode_list(inst_var_sub::in, list(term)::in,
list(type_and_mode)::out) is semidet.
convert_type_and_mode_list(_, [], []).
convert_type_and_mode_list(InstConstraints, [H0 | T0], [H | T]) :-
convert_type_and_mode(InstConstraints, H0, H),
convert_type_and_mode_list(InstConstraints, T0, T).
:- pred convert_type_and_mode(inst_var_sub::in, term::in, type_and_mode::out)
is semidet.
convert_type_and_mode(InstConstraints, Term, Result) :-
( Term = term.functor(term.atom("::"), [TypeTerm, ModeTerm], _Context) ->
parse_type(TypeTerm, ok1(Type)),
convert_mode(allow_constrained_inst_var, ModeTerm, Mode0),
constrain_inst_vars_in_mode(InstConstraints, Mode0, Mode),
Result = type_and_mode(Type, Mode)
;
parse_type(Term, ok1(Type)),
Result = type_only(Type)
).
:- pred make_mode_defn(varset::in, condition::in, processed_mode_body::in,
item::out) is det.
make_mode_defn(VarSet0, Cond, processed_mode_body(Name, Params, ModeDefn),
item_mode_defn(VarSet, Name, Params, ModeDefn, Cond)) :-
varset.coerce(VarSet0, VarSet).
%-----------------------------------------------------------------------------%
:- type maker(T1, T2) == pred(T1, T2).
:- mode maker == (pred(in, out) is det).
:- pred parse_symlist_decl(parser(T)::parser, maker(list(T), sym_list)::maker,
maker(sym_list, module_defn)::maker,
term::in, decl_attrs::in, varset::in, maybe1(item)::out) is det.
parse_symlist_decl(ParserPred, MakeSymListPred, MakeModuleDefnPred,
Term, Attributes, VarSet, Result) :-
parse_list(ParserPred, Term, Result0),
process_maybe1(make_module_defn(MakeSymListPred, MakeModuleDefnPred,
VarSet), Result0, Result1),
check_no_attributes(Result1, Attributes, Result).
:- pred make_module_defn(maker(T, sym_list)::maker,
maker(sym_list, module_defn)::maker, varset::in, T::in, item::out)
is det.
make_module_defn(MakeSymListPred, MakeModuleDefnPred, VarSet0, T,
item_module_defn(VarSet, ModuleDefn)) :-
varset.coerce(VarSet0, VarSet),
call(MakeSymListPred, T, SymList),
call(MakeModuleDefnPred, SymList, ModuleDefn).
%-----------------------------------------------------------------------------%
:- pred process_maybe1(maker(T1, T2)::maker, maybe1(T1)::in, maybe1(T2)::out)
is det.
process_maybe1(Maker, ok1(X), ok1(Y)) :-
call(Maker, X, Y).
process_maybe1(_, error1(Errors), error1(Errors)).
:- pred process_maybe1_to_t(maker(T1, maybe1(T2))::maker,
maybe1(T1)::in, maybe1(T2)::out) is det.
process_maybe1_to_t(Maker, ok1(X), Y) :-
call(Maker, X, Y).
process_maybe1_to_t(_, error1(Errors), error1(Errors)).
%-----------------------------------------------------------------------------%
:- pred make_module(list(module_specifier)::in, sym_list::out) is det.
make_module(X, list_module(X)).
:- pred make_sym(list(sym_specifier)::in, sym_list::out) is det.
make_sym(X, list_sym(X)).
:- pred make_pred(list(pred_specifier)::in, sym_list::out) is det.
make_pred(X, list_pred(X)).
:- pred make_func(list(func_specifier)::in, sym_list::out) is det.
make_func(X, list_func(X)).
:- pred make_cons(list(cons_specifier)::in, sym_list::out) is det.
make_cons(X, list_cons(X)).
:- pred make_type(list(type_specifier)::in, sym_list::out) is det.
make_type(X, list_type(X)).
:- pred make_adt(list(adt_specifier)::in, sym_list::out) is det.
make_adt(X, list_adt(X)).
:- pred make_op(list(op_specifier)::in, sym_list::out) is det.
make_op(X, list_op(X)).
%-----------------------------------------------------------------------------%
%
% A symbol specifier is one of
%
% SymbolNameSpecifier
% Matches any symbol matched by the SymbolNameSpecifier.
% TypedConstructorSpecifier
% Matches any constructors matched by the
% TypedConstructorSpecifier.
% cons(ConstructorSpecifier)
% Matches only constructors.
% pred(PredSpecifier)
% Matches only predicates, ie. constructors of type `pred'.
% adt(SymbolNameSpecifier)
% Matches only type names.
% type(SymbolNameSpecifier)
% Matches type names matched by the SymbolNameSpecifier,
% and also matches any constructors for the matched type names.
% op(SymbolNameSpecifier)
% Matches only operators.
% module(ModuleSpecifier)
% Matches all symbols in the specified module.
:- pred parse_symbol_specifier(term::in, maybe1(sym_specifier)::out) is det.
parse_symbol_specifier(MainTerm, Result) :-
( MainTerm = term.functor(term.atom(Functor), [Term], _Context) ->
( Functor = "cons" ->
parse_constructor_specifier(Term, Result0),
process_maybe1(make_cons_symbol_specifier, Result0, Result)
; Functor = "pred" ->
parse_predicate_specifier(Term, Result0),
process_maybe1(make_pred_symbol_specifier, Result0, Result)
; Functor = "func" ->
parse_function_specifier(Term, Result0),
process_maybe1(make_func_symbol_specifier, Result0, Result)
; Functor = "type" ->
parse_type_specifier(Term, Result0),
process_maybe1(make_type_symbol_specifier, Result0, Result)
; Functor = "adt" ->
parse_adt_specifier(Term, Result0),
process_maybe1(make_adt_symbol_specifier, Result0, Result)
; Functor = "op" ->
parse_op_specifier(Term, Result0),
process_maybe1(make_op_symbol_specifier, Result0, Result)
; Functor = "module" ->
parse_module_specifier(Term, Result0),
process_maybe1(make_module_symbol_specifier, Result0, Result)
;
parse_constructor_specifier(MainTerm, Result0),
process_maybe1(make_cons_symbol_specifier, Result0, Result)
)
;
parse_constructor_specifier(MainTerm, Result0),
process_maybe1(make_cons_symbol_specifier, Result0, Result)
).
% Once we've parsed the appropriate type of symbol specifier, we need to
% convert it to a sym_specifier.
%
:- pred make_pred_symbol_specifier(pred_specifier::in, sym_specifier::out)
is det.
make_pred_symbol_specifier(PredSpec, spec_pred(PredSpec)).
:- pred make_func_symbol_specifier(func_specifier::in, sym_specifier::out)
is det.
make_func_symbol_specifier(FuncSpec, spec_func(FuncSpec)).
:- pred make_cons_symbol_specifier(cons_specifier::in, sym_specifier::out)
is det.
make_cons_symbol_specifier(ConsSpec, spec_cons(ConsSpec)).
:- pred make_type_symbol_specifier(type_specifier::in, sym_specifier::out)
is det.
make_type_symbol_specifier(TypeSpec, spec_type(TypeSpec)).
:- pred make_adt_symbol_specifier(adt_specifier::in, sym_specifier::out)
is det.
make_adt_symbol_specifier(ADT_Spec, spec_adt(ADT_Spec)).
:- pred make_op_symbol_specifier(op_specifier::in, sym_specifier::out) is det.
make_op_symbol_specifier(OpSpec, spec_op(OpSpec)).
:- pred make_module_symbol_specifier(module_specifier::in, sym_specifier::out)
is det.
make_module_symbol_specifier(ModuleSpec, spec_module(ModuleSpec)).
:- pred cons_specifier_to_sym_specifier(cons_specifier::in,
sym_specifier::out) is det.
cons_specifier_to_sym_specifier(consspec_sym(SymSpec), spec_sym(SymSpec)).
cons_specifier_to_sym_specifier(consspec_typed(SymSpec),
spec_typed_sym(SymSpec)).
%-----------------------------------------------------------------------------%
% A ModuleSpecifier is just an sym_name.
%
:- pred parse_module_specifier(term::in, maybe1(module_specifier)::out) is det.
parse_module_specifier(Term, Result) :-
parse_symbol_name(Term, Result).
% A ModuleName is an implicitly-quantified sym_name.
%
% We check for module names starting with capital letters as a special
% case, so that we can report a better error message for that case.
%
:- pred parse_module_name(module_name::in, term::in,
maybe1(module_name)::out) is det.
parse_module_name(DefaultModuleName, Term, Result) :-
( Term = term.variable(_, _) ->
dummy_term(ErrorContext),
Msg = "module names starting with capital letters " ++
"must be quoted using single quotes (e.g. "":- module 'Foo'."")",
Result = error1([Msg - ErrorContext])
;
parse_implicitly_qualified_symbol_name(DefaultModuleName, Term, Result)
).
%-----------------------------------------------------------------------------%
% A ConstructorSpecifier is one of
% SymbolNameSpecifier
% TypedConstructorSpecifier
%
% A TypedConstructorSpecifier is one of
% SymbolNameSpecifier::Type
% Matches only constructors with the specified result type.
% SymbolName(ArgType1, ..., ArgTypeN)
% Matches only constructors with the specified argument types.
% SymbolName(ArgType1, ..., ArgTypeN)::Type
% Matches only constructors with the specified argument
% and result types.
%
:- pred parse_constructor_specifier(term::in, maybe1(cons_specifier)::out)
is det.
parse_constructor_specifier(Term, Result) :-
(
Term = term.functor(term.atom("::"), [NameArgsTerm, TypeTerm],
_Context)
->
parse_arg_types_specifier(NameArgsTerm, NameArgsResult),
parse_type(TypeTerm, TypeResult),
process_typed_constructor_specifier(NameArgsResult, TypeResult, Result)
;
parse_arg_types_specifier(Term, TermResult),
process_maybe1(make_untyped_cons_spec, TermResult, Result)
).
%-----------------------------------------------------------------------------%
% A PredicateSpecifier is one of
% SymbolName(ArgType1, ..., ArgTypeN)
% Matches only predicates with the specified argument types.
% SymbolNameSpecifier
%
:- pred parse_predicate_specifier(term::in, maybe1(pred_specifier)::out)
is det.
parse_predicate_specifier(Term, Result) :-
( Term = term.functor(term.atom("/"), [_, _], _Context) ->
parse_symbol_name_specifier(Term, NameResult),
process_maybe1(make_arity_predicate_specifier, NameResult, Result)
;
parse_qualified_term(Term, Term, "predicate specifier", TermResult),
process_typed_predicate_specifier(TermResult, Result)
).
:- pred process_typed_predicate_specifier(maybe_functor::in,
maybe1(pred_specifier)::out) is det.
process_typed_predicate_specifier(ok2(Name, Args0), Result) :-
(
Args0 = [],
Result = ok1(predspec_sym(name(Name)))
;
Args0 = [_ | _],
parse_types(Args0, ArgsResult),
(
ArgsResult = ok1(Args),
Result = ok1(predspec_name_args(Name, Args))
;
ArgsResult = error1(Errors),
Result = error1(Errors)
)
).
process_typed_predicate_specifier(error2(Errors), error1(Errors)).
:- pred make_arity_predicate_specifier(sym_name_specifier::in,
pred_specifier::out) is det.
make_arity_predicate_specifier(Result, predspec_sym(Result)).
%-----------------------------------------------------------------------------%
% Parsing the name & argument types of a constructor specifier is exactly
% the same as parsing a predicate specifier...
%
:- pred parse_arg_types_specifier(term::in, maybe1(pred_specifier)::out)
is det.
parse_arg_types_specifier(Term, Result) :-
( Term = term.functor(term.atom("/"), [_, _], _Context) ->
parse_symbol_name_specifier(Term, NameResult),
process_maybe1(make_arity_predicate_specifier, NameResult, Result)
;
parse_qualified_term(Term, Term, "constructor specifier", TermResult),
process_typed_predicate_specifier(TermResult, Result)
).
% ... but we have to convert the result back into the appropriate format.
%
:- pred process_typed_constructor_specifier(maybe1(pred_specifier)::in,
maybe1(mer_type)::in, maybe1(cons_specifier)::out) is det.
process_typed_constructor_specifier(error1(Errors1), error1(Errors2),
error1(Errors1 ++ Errors2)).
process_typed_constructor_specifier(error1(Errors), ok1(_), error1(Errors)).
process_typed_constructor_specifier(ok1(_), error1(Errors), error1(Errors)).
process_typed_constructor_specifier(ok1(NameArgs), ok1(ResType),
ok1(Result)) :-
process_typed_cons_spec_2(NameArgs, ResType, Result).
:- pred process_typed_cons_spec_2(pred_specifier::in, mer_type::in,
cons_specifier::out) is det.
process_typed_cons_spec_2(predspec_sym(Name), Res,
consspec_typed(name_res(Name, Res))).
process_typed_cons_spec_2(predspec_name_args(Name, Args), Res,
consspec_typed(name_args_res(Name, Args, Res))).
:- pred make_untyped_cons_spec(pred_specifier::in, cons_specifier::out) is det.
make_untyped_cons_spec(predspec_sym(Name),
consspec_sym(Name)).
make_untyped_cons_spec(predspec_name_args(Name, Args),
consspec_typed(name_args(Name, Args))).
%-----------------------------------------------------------------------------%
% A SymbolNameSpecifier is one of
% SymbolName
% SymbolName/Arity
% Matches only symbols of the specified arity.
%
:- pred parse_symbol_name_specifier(term::in, maybe1(sym_name_specifier)::out)
is det.
parse_symbol_name_specifier(Term, Result) :-
root_module_name(DefaultModule),
parse_implicitly_qualified_symbol_name_specifier(DefaultModule, Term,
Result).
:- pred parse_implicitly_qualified_symbol_name_specifier(module_name::in,
term::in, maybe1(sym_name_specifier)::out) is det.
parse_implicitly_qualified_symbol_name_specifier(DefaultModule, Term,
Result) :-
( Term = term.functor(term.atom("/"), [NameTerm, ArityTerm], _Context) ->
( ArityTerm = term.functor(term.integer(Arity), [], _Context2) ->
( Arity >= 0 ->
parse_implicitly_qualified_symbol_name(DefaultModule, NameTerm,
NameResult),
process_maybe1(make_name_arity_specifier(Arity),
NameResult, Result)
;
Msg = "arity in symbol name specifier " ++
"must be a non-negative integer",
Result = error1([Msg - Term])
)
;
Msg = "arity in symbol name specifier must be an integer",
Result = error1([Msg - Term])
)
;
parse_implicitly_qualified_symbol_name(DefaultModule, Term,
SymbolNameResult),
process_maybe1(make_name_specifier, SymbolNameResult, Result)
).
:- pred make_name_arity_specifier(arity::in, sym_name::in,
sym_name_specifier::out) is det.
make_name_arity_specifier(Arity, Name, name_arity(Name, Arity)).
:- pred make_name_specifier(sym_name::in, sym_name_specifier::out) is det.
make_name_specifier(Name, name(Name)).
%-----------------------------------------------------------------------------%
% A SymbolName is one of
% Name
% Matches symbols with the specified name in the
% current namespace.
% Module.Name
% Matches symbols with the specified name exported
% by the specified module (where Module is itself a SymbolName).
%
% We also allow the syntax `Module__Name' as an alternative
% for `Module.Name'.
%
:- pred parse_symbol_name(term(T)::in, maybe1(sym_name)::out) is det.
parse_symbol_name(Term, Result) :-
(
Term = term.functor(term.atom(FunctorName), [ModuleTerm, NameTerm],
_Context),
( FunctorName = ":"
; FunctorName = "."
)
->
( NameTerm = term.functor(term.atom(Name), [], _Context1) ->
parse_symbol_name(ModuleTerm, ModuleResult),
(
ModuleResult = ok1(Module),
Result = ok1(qualified(Module, Name))
;
ModuleResult = error1(_),
term.coerce(Term, ErrorTerm),
Msg = "module name identifier expected before" ++
"'" ++ FunctorName ++ "' " ++ "in qualified symbol name",
Result = error1([Msg - ErrorTerm])
)
;
term.coerce(Term, ErrorTerm),
Msg = "identifier expected after '" ++ FunctorName ++ "' " ++
"in qualified symbol name",
Result = error1([Msg - ErrorTerm])
)
;
( Term = term.functor(term.atom(Name), [], _Context3) ->
SymName = string_to_sym_name_sep(Name, "__"),
Result = ok1(SymName)
;
term.coerce(Term, ErrorTerm),
Result = error1(["symbol name expected" - ErrorTerm])
)
).
:- pred parse_implicitly_qualified_symbol_name(module_name::in, term::in,
maybe1(sym_name)::out) is det.
parse_implicitly_qualified_symbol_name(DefaultModName, Term, Result) :-
parse_symbol_name(Term, Result0),
(
Result0 = ok1(SymName),
(
root_module_name(DefaultModName)
->
Result = Result0
;
SymName = qualified(ModName, _),
\+ match_sym_name(ModName, DefaultModName)
->
Msg = "module qualifier in definition " ++
"does not match preceding `:- module' declaration",
Result = error1([Msg - Term])
;
UnqualName = unqualify_name(SymName),
Result = ok1(qualified(DefaultModName, UnqualName))
)
;
Result0 = error1(_),
Result = Result0
).
%-----------------------------------------------------------------------------%
sym_name_and_args(Term, SymName, Args) :-
parse_qualified_term(Term, Term, "", ok2(SymName, Args)).
parse_implicitly_qualified_term(DefaultModName, Term, ContainingTerm, Msg,
Result) :-
parse_qualified_term(Term, ContainingTerm, Msg, Result0),
( Result0 = ok2(SymName, Args) ->
(
root_module_name(DefaultModName)
->
Result = Result0
;
SymName = qualified(ModName, _),
\+ match_sym_name(ModName, DefaultModName)
->
term.coerce(Term, ErrorTerm),
ErrorMsg = "module qualifier in definition does not match " ++
"preceding `:- module' declaration",
Result = error2([ErrorMsg - ErrorTerm])
;
UnqualName = unqualify_name(SymName),
Result = ok2(qualified(DefaultModName, UnqualName), Args)
)
;
Result = Result0
).
parse_qualified_term(Term, ContainingTerm, Msg, Result) :-
(
Term = term.functor(term.atom(FunctorName),
[ModuleTerm, NameArgsTerm], _),
FunctorName = "."
->
( NameArgsTerm = term.functor(term.atom(Name), Args, _) ->
parse_symbol_name(ModuleTerm, ModuleResult),
(
ModuleResult = ok1(Module),
Result = ok2(qualified(Module, Name), Args)
;
ModuleResult = error1(_),
term.coerce(Term, ErrorTerm),
ErrorMsg = "module name identifier expected before '.' " ++
"in qualified symbol name",
Result = error2([ErrorMsg - ErrorTerm])
)
;
term.coerce(Term, ErrorTerm),
ErrorMsg = "identifier expected after '.' " ++
"in qualified symbol name",
Result = error2([ErrorMsg - ErrorTerm])
)
;
( Term = term.functor(term.atom(Name), Args, _) ->
SymName = string_to_sym_name_sep(Name, "__"),
Result = ok2(SymName, Args)
;
string.append("atom expected in ", Msg, ErrorMsg),
% Since variables don't have any term.context, if Term is
% a variable, we use ContainingTerm instead (hopefully that
% _will_ have a term.context).
( Term = term.variable(_, _) ->
ErrorTerm0 = ContainingTerm
;
ErrorTerm0 = Term
),
term.coerce(ErrorTerm0, ErrorTerm),
Result = error2([ErrorMsg - ErrorTerm])
)
).
%-----------------------------------------------------------------------------%
%
% Predicates used to convert a sym_list to a program item.
:- pred make_use(sym_list::in, module_defn::out) is det.
make_use(Syms, md_use(Syms)).
:- pred make_import(sym_list::in, module_defn::out) is det.
make_import(Syms, md_import(Syms)).
:- pred make_export(sym_list::in, module_defn::out) is det.
make_export(Syms, md_export(Syms)).
%-----------------------------------------------------------------------------%
% A FuncSpecifier is just a constructur name specifier.
%
:- pred parse_function_specifier(term::in, maybe1(func_specifier)::out) is det.
parse_function_specifier(Term, Result) :-
parse_constructor_specifier(Term, Result).
% A TypeSpecifier is just a symbol name specifier.
%
:- pred parse_type_specifier(term::in, maybe1(sym_name_specifier)::out) is det.
parse_type_specifier(Term, Result) :-
parse_symbol_name_specifier(Term, Result).
% An ADT_Specifier is just a symbol name specifier.
%
:- pred parse_adt_specifier(term::in, maybe1(sym_name_specifier)::out) is det.
parse_adt_specifier(Term, Result) :-
parse_symbol_name_specifier(Term, Result).
%-----------------------------------------------------------------------------%
% For the moment, an OpSpecifier is just a symbol name specifier.
% XXX We should allow specifying the fixity of an operator
%
:- pred parse_op_specifier(term::in, maybe1(op_specifier)::out) is det.
parse_op_specifier(Term, Result) :-
parse_symbol_name_specifier(Term, R),
process_maybe1(make_op_specifier, R, Result).
:- pred make_op_specifier(sym_name_specifier::in, op_specifier::out) is det.
make_op_specifier(X, opspec_sym(X)).
%-----------------------------------------------------------------------------%
:- func convert_constructor_arg_list(module_name, list(term)) =
maybe1(list(constructor_arg)).
convert_constructor_arg_list(_ModuleName, []) = ok1([]).
convert_constructor_arg_list( ModuleName, [Term | Terms]) = Result :-
( Term = term.functor(term.atom("::"), [NameTerm, TypeTerm], _) ->
parse_implicitly_qualified_term(ModuleName, NameTerm, Term,
"field name", NameResult),
(
NameResult = error2(Errors),
Result = error1(Errors)
;
NameResult = ok2(SymName, SymNameArgs),
(
SymNameArgs = [_ | _],
Result = error1(["syntax error in constructor name" - Term])
;
SymNameArgs = [],
MaybeFieldName = yes(SymName),
Result = convert_constructor_arg_list_2(ModuleName,
MaybeFieldName, TypeTerm, Terms)
)
)
;
MaybeFieldName = no,
TypeTerm = Term,
Result = convert_constructor_arg_list_2(ModuleName, MaybeFieldName,
TypeTerm, Terms)
).
:- func convert_constructor_arg_list_2(module_name, maybe(sym_name), term,
list(term)) = maybe1(list(constructor_arg)).
convert_constructor_arg_list_2(ModuleName, MaybeFieldName, TypeTerm, Terms) =
Result :-
parse_type(TypeTerm, TypeResult),
(
TypeResult = ok1(Type),
Context = term_context(TypeTerm),
Arg = ctor_arg(MaybeFieldName, Type, Context),
Result0 = convert_constructor_arg_list(ModuleName, Terms),
(
Result0 = error1(Errors),
Result = error1(Errors)
;
Result0 = ok1(Args),
Result = ok1([Arg | Args])
)
;
TypeResult = error1(Errors),
Result = error1(Errors)
).
%-----------------------------------------------------------------------------%
% We use the empty module name ('') as the "root" module name; when adding
% default module qualifiers in parse_implicitly_qualified_{term,symbol},
% if the default module is the root module then we don't add any qualifier.
%
:- pred root_module_name(module_name::out) is det.
root_module_name(unqualified("")).
%-----------------------------------------------------------------------------%
:- func this_file = string.
this_file = "prog_io.m".
%-----------------------------------------------------------------------------%